Merge branch 'develop' into fix/TD-6442

e9f0d8c9 · jiajingbin · 4199c826 · d2f514ee · e9f0d8c9 · e9f0d8c9
73 changed file
--- a/Jenkinsfile
+++ b/Jenkinsfile
@@ -234,11 +234,12 @@ pipeline {
              cd ${WKC}/tests/examples/nodejs
              npm install td2.0-connector > /dev/null 2>&1
              node nodejsChecker.js host=localhost
+              node test1970.js
              '''
              sh '''
                cd ${WKC}/tests/examples/C#/taosdemo
                mcs -out:taosdemo *.cs > /dev/null 2>&1
-                echo '' |./taosdemo
+                echo '' |./taosdemo -c /etc/taos
              '''
              sh '''
                cd ${WKC}/tests/gotest
@@ -256,13 +257,11 @@ pipeline {
          steps {
            pre_test()
-            catchError(buildResult: 'SUCCESS', stageResult: 'FAILURE') {
+            timeout(time: 60, unit: 'MINUTES'){
-                timeout(time: 60, unit: 'MINUTES'){
+              sh '''
-                  sh '''
+              cd ${WKC}/tests/pytest
-                  cd ${WKC}/tests/pytest
+              ./crash_gen.sh -a -p -t 4 -s 2000
-                  ./crash_gen.sh -a -p -t 4 -s 2000
+              '''
-                  '''
-                }
            }
            timeout(time: 60, unit: 'MINUTES'){
              // sh '''
@@ -453,4 +452,4 @@ pipeline {
            )
        }
    } 
 }
\ No newline at end of file
--- a/cmake/define.inc
+++ b/cmake/define.inc
@@ -133,8 +133,10 @@ IF (TD_LINUX)
  IF (TD_MEMORY_SANITIZER)
    SET(DEBUG_FLAGS "-fsanitize=address -fsanitize=undefined -fno-sanitize-recover=all -fsanitize=float-divide-by-zero -fsanitize=float-cast-overflow -fno-sanitize=null -fno-sanitize=alignment -static-libasan -O0 -g3 -DDEBUG")
+    MESSAGE(STATUS "memory sanitizer detected as true")
  ELSE ()
    SET(DEBUG_FLAGS "-O0 -g3 -DDEBUG")
+    MESSAGE(STATUS "memory sanitizer detected as false")
  ENDIF ()
  SET(RELEASE_FLAGS "-O3 -Wno-error")

--- a/cmake/version.inc
+++ b/cmake/version.inc
@@ -86,7 +86,7 @@ ENDIF ()
 MESSAGE(STATUS "============= compile version parameter information start ============= ")
 MESSAGE(STATUS "ver number:" ${TD_VER_NUMBER})
 MESSAGE(STATUS "compatible ver number:" ${TD_VER_COMPATIBLE})
-MESSAGE(STATUS "communit commit id:" ${TD_VER_GIT})
+MESSAGE(STATUS "community commit id:" ${TD_VER_GIT})
 MESSAGE(STATUS "internal commit id:" ${TD_VER_GIT_INTERNAL})
 MESSAGE(STATUS "build date:" ${TD_VER_DATE})
 MESSAGE(STATUS "ver type:" ${TD_VER_VERTYPE})

--- a/documentation20/cn/02.getting-started/docs.md
+++ b/documentation20/cn/02.getting-started/docs.md
@@ -208,7 +208,7 @@ taos> select avg(current), max(voltage), min(phase) from test.d10 interval(10s);
 | **C#**      | ●               | ●         | ○         | ○               | ○         | ○         | ○                   | --                   | --                 |
 | **RESTful** | ●               | ●         | ●         | ●               | ●         | ●         | ●                   | ●                    | ●                  |
-注： ● 表示经过官方测试验证， ○ 表示非官方测试验证。
+注：● 表示官方测试验证通过，○ 表示非官方测试验证通过，-- 表示未经验证。
 请跳转到 [连接器](https://www.taosdata.com/cn/documentation/connector) 查看更详细的信息。
--- a/documentation20/cn/04.model/docs.md
+++ b/documentation20/cn/04.model/docs.md
@@ -43,7 +43,7 @@ CREATE STABLE meters (ts timestamp, current float, voltage int, phase float) TAG
 每一种类型的数据采集点需要建立一个超级表，因此一个物联网系统，往往会有多个超级表。对于电网，我们就需要对智能电表、变压器、母线、开关等都建立一个超级表。在物联网中，一个设备就可能有多个数据采集点（比如一台风力发电的风机，有的采集点采集电流、电压等电参数，有的采集点采集温度、湿度、风向等环境参数），这个时候，对这一类型的设备，需要建立多张超级表。一张超级表里包含的采集物理量必须是同时采集的（时间戳是一致的）。
-一张超级表最多容许1024列，如果一个采集点采集的物理量个数超过1024，需要建多张超级表来处理。一个系统可以有多个DB，一个DB里可以有一到多个超级表。
+一张超级表最多容许 1024 列，如果一个采集点采集的物理量个数超过 1024，需要建多张超级表来处理。一个系统可以有多个 DB，一个 DB 里可以有一到多个超级表。（从 2.1.7.0 版本开始，列数限制由 1024 列放宽到了 4096 列。）
 ## <a class="anchor" id="create-table"></a>创建表

--- a/documentation20/cn/08.connector/01.java/docs.md
+++ b/documentation20/cn/08.connector/01.java/docs.md
@@ -46,7 +46,7 @@ TDengine 的 JDBC 驱动实现尽可能与关系型数据库驱动保持一致
 </tr>
 </table>
-注意：与 JNI 方式不同，RESTful 接口是无状态的。在使用JDBC-RESTful时，需要在sql中指定表、超级表的数据库名称。（从 TDengine 2.1.8.0 版本开始，也可以在 RESTful url 中指定当前 SQL 语句所使用的默认数据库名。）例如：
+注意：与 JNI 方式不同，RESTful 接口是无状态的。在使用JDBC-RESTful时，需要在sql中指定表、超级表的数据库名称。（从 TDengine 2.2.0.0 版本开始，也可以在 RESTful url 中指定当前 SQL 语句所使用的默认数据库名。）例如：
 ```sql
 INSERT INTO test.t1 USING test.weather (ts, temperature) TAGS('beijing') VALUES(now, 24.6);
 ```

--- a/documentation20/cn/08.connector/docs.md
+++ b/documentation20/cn/08.connector/docs.md
@@ -17,7 +17,7 @@ TDengine提供了丰富的应用程序开发接口，其中包括C/C++、Java、
 | **C#**      | ●               | ●               | ○               | ○               | ○         | ○         | ○               | --               | --             |
 | **RESTful** | ●               | ●               | ●               | ●               | ●         | ●         | ○               | ○                | ○              |
-其中 ● 表示经过官方测试验证， ○ 表示非官方测试验证。
+其中 ● 表示官方测试验证通过，○ 表示非官方测试验证通过，-- 表示未经验证。
 注意：
@@ -654,7 +654,7 @@ conn.close()
 为支持各种不同类型平台的开发，TDengine 提供符合 REST 设计标准的 API，即 RESTful API。为最大程度降低学习成本，不同于其他数据库 RESTful API 的设计方法，TDengine 直接通过 HTTP POST 请求 BODY 中包含的 SQL 语句来操作数据库，仅需要一个 URL。RESTful 连接器的使用参见[视频教程](https://www.taosdata.com/blog/2020/11/11/1965.html)。
-注意：与标准连接器的一个区别是，RESTful 接口是无状态的，因此 `USE db_name` 指令没有效果，所有对表名、超级表名的引用都需要指定数据库名前缀。（从 2.1.8.0 版本开始，支持在 RESTful url 中指定 db_name，这时如果 SQL 语句中没有指定数据库名前缀的话，会使用 url 中指定的这个 db_name。）
+注意：与标准连接器的一个区别是，RESTful 接口是无状态的，因此 `USE db_name` 指令没有效果，所有对表名、超级表名的引用都需要指定数据库名前缀。（从 2.2.0.0 版本开始，支持在 RESTful url 中指定 db_name，这时如果 SQL 语句中没有指定数据库名前缀的话，会使用 url 中指定的这个 db_name。）
 ### 安装
@@ -695,7 +695,7 @@ http://<fqdn>:<port>/rest/sql/[db_name]
 - fqnd: 集群中的任一台主机 FQDN 或 IP 地址
 - port: 配置文件中 httpPort 配置项，缺省为 6041
- db_name: 可选参数，指定本次所执行的 SQL 语句的默认数据库库名。（从 2.1.8.0 版本开始支持）
+- db_name: 可选参数，指定本次所执行的 SQL 语句的默认数据库库名。（从 2.2.0.0 版本开始支持）
 例如：http://h1.taos.com:6041/rest/sql/test 是指向地址为 h1.taos.com:6041 的 url，并将默认使用的数据库库名设置为 test。
@@ -984,15 +984,18 @@ go build
 ### Go连接器的使用
-TDengine提供了GO驱动程序包`taosSql`.`taosSql`实现了GO语言的内置接口`database/sql/driver`。用户只需按如下方式引入包就可以在应用程序中访问TDengine。
+TDengine提供了GO驱动程序包`taosSql`。`taosSql`实现了GO语言的内置接口`database/sql/driver`。用户只需按如下方式引入包就可以在应用程序中访问TDengine。
 ```go
 import (
  "database/sql"
-  _ "github.com/taosdata/driver-go/taosSql"
+  _ "github.com/taosdata/driver-go/v2/taosSql"
 )
 ```
 **提示**：下划线与双引号之间必须有一个空格。
+`taosSql` 的 v2 版本进行了重构，分离出内置数据库操作接口 `database/sql/driver` 到目录 `taosSql`；订阅、stmt等其他功能放到目录 `af`。
 ### 常用API
 - `sql.Open(DRIVER_NAME string, dataSourceName string) *DB` 

--- a/documentation20/cn/10.cluster/docs.md
+++ b/documentation20/cn/10.cluster/docs.md
@@ -14,7 +14,7 @@ TDengine的集群管理极其简单，除添加和删除节点需要人工干预
 **第一步**：如果搭建集群的物理节点中，存有之前的测试数据、装过1.X的版本，或者装过其他版本的TDengine，请先将其删除，并清空所有数据（如果需要保留原有数据，请联系涛思交付团队进行旧版本升级、数据迁移），具体步骤请参考博客[《TDengine多种安装包的安装和卸载》](https://www.taosdata.com/blog/2019/08/09/566.html)。   
 **注意1：**因为FQDN的信息会写进文件，如果之前没有配置或者更改FQDN，且启动了TDengine。请一定在确保数据无用或者备份的前提下，清理一下之前的数据（`rm -rf /var/lib/taos/*`）；  
-**注意2：**客户端也需要配置，确保它可以正确解析每个节点的FQDN配置，不管是通过DNS服务，还是 Host 文件。
+**注意2：**客户端也需要配置，确保它可以正确解析每个节点的FQDN配置，不管是通过DNS服务，还是修改 hosts 文件。
 **第二步**：建议关闭所有物理节点的防火墙，至少保证端口：6030 - 6042的TCP和UDP端口都是开放的。**强烈建议**先关闭防火墙，集群搭建完毕之后，再来配置端口；
@@ -79,13 +79,13 @@ Query OK, 1 row(s) in set (0.006385s)
 taos>
 ```
-上述命令里，可以看到这个刚启动的这个数据节点的End Point是：h1.taos.com:6030，就是这个新集群的firstEP。
+上述命令里，可以看到这个刚启动的这个数据节点的End Point是：h1.taos.com:6030，就是这个新集群的firstEp。
 ## <a class="anchor" id="node-other"></a>启动后续数据节点
 将后续的数据节点添加到现有集群，具体有以下几步：
-1. 按照[《立即开始》](https://www.taosdata.com/cn/documentation/getting-started/)一章的方法在每个物理节点启动taosd；（注意：每个物理节点都需要在 taos.cfg 文件中将 firstEP 参数配置为新集群首个节点的 End Point——在本例中是 h1.taos.com:6030）
+1. 按照[《立即开始》](https://www.taosdata.com/cn/documentation/getting-started/)一章的方法在每个物理节点启动taosd；（注意：每个物理节点都需要在 taos.cfg 文件中将 firstEp参数配置为新集群首个节点的 End Point——在本例中是 h1.taos.com:6030）
 2. 在第一个数据节点，使用CLI程序taos，登录进TDengine系统，执行命令：
@@ -110,7 +110,7 @@ taos>
 **提示：**
- 任何已经加入集群在线的数据节点，都可以作为后续待加入节点的 firstEP。
+- 任何已经加入集群在线的数据节点，都可以作为后续待加入节点的 firstEp。
 - firstEp 这个参数仅仅在该数据节点首次加入集群时有作用，加入集群后，该数据节点会保存最新的 mnode 的 End Point 列表，不再依赖这个参数。
  - 接下来，配置文件中的 firstEp 参数就主要在客户端连接的时候使用了，例如 taos shell 如果不加参数，会默认连接由 firstEp 指定的节点。
 - 两个没有配置 firstEp 参数的数据节点 dnode 启动后，会独立运行起来。这个时候，无法将其中一个数据节点加入到另外一个数据节点，形成集群。**无法将两个独立的集群合并成为新的集群**。
@@ -119,9 +119,14 @@ taos>
 上面已经介绍如何从零开始搭建集群。集群组建完后，还可以随时添加新的数据节点进行扩容，或删除数据节点，并检查集群当前状态。
+**提示：**
+- 以下所有执行命令的操作需要先登陆进TDengine系统，必要时请使用root权限。
 ### 添加数据节点
-执行CLI程序taos，使用root账号登录进系统，执行：
+执行CLI程序taos，执行：
 ```
 CREATE DNODE "fqdn:port"; 
@@ -131,7 +136,7 @@ CREATE DNODE "fqdn:port";
 ### 删除数据节点
-执行CLI程序taos，使用root账号登录进TDengine系统，执行：
+执行CLI程序taos，执行：
 ```mysql
 DROP DNODE "fqdn:port | dnodeID";
@@ -153,7 +158,7 @@ DROP DNODE "fqdn:port | dnodeID";
 手动将某个vnode迁移到指定的dnode。
-执行CLI程序taos，使用root账号登录进TDengine系统，执行：
+执行CLI程序taos，执行：
 ```mysql
 ALTER DNODE <source-dnodeId> BALANCE "VNODE:<vgId>-DNODE:<dest-dnodeId>";
@@ -169,7 +174,7 @@ ALTER DNODE <source-dnodeId> BALANCE "VNODE:<vgId>-DNODE:<dest-dnodeId>";
 ### 查看数据节点
-执行CLI程序taos，使用root账号登录进TDengine系统，执行：
+执行CLI程序taos，执行：
 ```mysql
 SHOW DNODES;
 ```
@@ -180,8 +185,9 @@ SHOW DNODES;
 为充分利用多核技术，并提供scalability，数据需要分片处理。因此TDengine会将一个DB的数据切分成多份，存放在多个vnode里。这些vnode可能分布在多个数据节点dnode里，这样就实现了水平扩展。一个vnode仅仅属于一个DB，但一个DB可以有多个vnode。vnode的是mnode根据当前系统资源的情况，自动进行分配的，无需任何人工干预。
-执行CLI程序taos，使用root账号登录进TDengine系统，执行：
+执行CLI程序taos，执行：
 ```mysql
+USE SOME_DATABASE;
 SHOW VGROUPS;
 ```

--- a/documentation20/cn/11.administrator/docs.md
+++ b/documentation20/cn/11.administrator/docs.md
@@ -652,7 +652,7 @@ rmtaos
 - 表名：不能包含“.”以及特殊字符，与所属数据库名一起，不能超过 192 个字符，每行数据最大长度 16k 个字符
 - 表的列名：不能包含特殊字符，不能超过 64 个字符
 - 数据库名、表名、列名，都不能以数字开头，合法的可用字符集是“英文字符、数字和下划线”
- 表的列数：不能超过 1024 列，最少需要 2 列，第一列必须是时间戳
+- 表的列数：不能超过 1024 列，最少需要 2 列，第一列必须是时间戳（从 2.1.7.0 版本开始，改为最多支持 4096 列）
 - 记录的最大长度：包括时间戳 8 byte，不能超过 16KB（每个 BINARY/NCHAR 类型的列还会额外占用 2 个 byte 的存储位置）
 - 单条 SQL 语句默认最大字符串长度：65480 byte，但可通过系统配置参数 maxSQLLength 修改，最长可配置为 1048576 byte
 - 数据库副本数：不能超过 3
@@ -665,7 +665,7 @@ rmtaos
 - 库的个数：仅受节点个数限制
 - 单个库上虚拟节点个数：不能超过 64 个
 - 库的数目，超级表的数目、表的数目，系统不做限制，仅受系统资源限制
- SELECT 语句的查询结果，最多允许返回 1024 列（语句中的函数调用可能也会占用一些列空间），超限时需要显式指定较少的返回数据列，以避免语句执行报错。
+- SELECT 语句的查询结果，最多允许返回 1024 列（语句中的函数调用可能也会占用一些列空间），超限时需要显式指定较少的返回数据列，以避免语句执行报错。（从 2.1.7.0 版本开始，改为最多允许 4096 列）
 目前 TDengine 有将近 200 个内部保留关键字，这些关键字无论大小写均不可以用作库名、表名、STable 名、数据列名及标签列名等。这些关键字列表如下：
@@ -800,7 +800,7 @@ taos -n sync -P 6042 -h <fqdn of server>
 `taos -n speed -h <fqdn of server> -P 6030 -N 10 -l 10000000 -S TCP`
-从 2.1.8.0 版本开始，taos 工具新提供了一个网络速度诊断的模式，可以对一个正在运行中的 taosd 实例或者 `taos -n server` 方式模拟的一个服务端实例，以非压缩传输的方式进行网络测速。这个模式下可供调整的参数如下：
+从 2.2.0.0 版本开始，taos 工具新提供了一个网络速度诊断的模式，可以对一个正在运行中的 taosd 实例或者 `taos -n server` 方式模拟的一个服务端实例，以非压缩传输的方式进行网络测速。这个模式下可供调整的参数如下：
 -n：设为“speed”时，表示对网络速度进行诊断。
 -h：所要连接的服务端的 FQDN 或 ip 地址。如果不设置这一项，会使用本机 taos.cfg 文件中 FQDN 参数的设置作为默认值。
@@ -813,7 +813,7 @@ taos -n sync -P 6042 -h <fqdn of server>
 `taos -n fqdn -h <fqdn of server>`
-从 2.1.8.0 版本开始，taos 工具新提供了一个 FQDN 解析速度的诊断模式，可以对一个目标 FQDN 地址尝试解析，并记录解析过程中所消耗的时间。这个模式下可供调整的参数如下：
+从 2.2.0.0 版本开始，taos 工具新提供了一个 FQDN 解析速度的诊断模式，可以对一个目标 FQDN 地址尝试解析，并记录解析过程中所消耗的时间。这个模式下可供调整的参数如下：
 -n：设为“fqdn”时，表示对 FQDN 解析进行诊断。
 -h：所要解析的目标 FQDN 地址。如果不设置这一项，会使用本机 taos.cfg 文件中 FQDN 参数的设置作为默认值。

--- a/documentation20/cn/12.taos-sql/docs.md
+++ b/documentation20/cn/12.taos-sql/docs.md
@@ -35,7 +35,7 @@ taos> DESCRIBE meters;
 - 内部函数 now 是客户端的当前时间
 - 插入记录时，如果时间戳为 now，插入数据时使用提交这条记录的客户端的当前时间
 - Epoch Time：时间戳也可以是一个长整数，表示从格林威治时间 1970-01-01 00:00:00.000 (UTC/GMT) 开始的毫秒数（相应地，如果所在 Database 的时间精度设置为“微秒”，则长整型格式的时间戳含义也就对应于从格林威治时间 1970-01-01 00:00:00.000 (UTC/GMT) 开始的微秒数；纳秒精度的逻辑也是类似的。）
- 时间可以加减，比如 now-2h，表明查询时刻向前推 2 个小时（最近 2 小时）。数字后面的时间单位可以是 b(纳秒)、u(微秒)、a(毫秒)、s(秒)、m(分)、h(小时)、d(天)、w(周)。 比如 `select * from t1 where ts > now-2w and ts <= now-1w`，表示查询两周前整整一周的数据。在指定降频操作（down sampling）的时间窗口（interval）时，时间单位还可以使用 n(自然月) 和 y(自然年)。
+- 时间可以加减，比如 now-2h，表明查询时刻向前推 2 个小时（最近 2 小时）。数字后面的时间单位可以是 b(纳秒)、u(微秒)、a(毫秒)、s(秒)、m(分)、h(小时)、d(天)、w(周)。 比如 `select * from t1 where ts > now-2w and ts <= now-1w`，表示查询两周前整整一周的数据。在指定降采样操作（down sampling）的时间窗口（interval）时，时间单位还可以使用 n(自然月) 和 y(自然年)。
 TDengine 缺省的时间戳是毫秒精度，但通过在 CREATE DATABASE 时传递的 PRECISION 参数就可以支持微秒和纳秒。（从 2.1.5.0 版本开始支持纳秒精度）
@@ -233,7 +233,7 @@ TDengine 缺省的时间戳是毫秒精度，但通过在 CREATE DATABASE 时传
    ```
    说明：
-    1) 列的最大个数为1024，最小个数为2；
+    1) 列的最大个数为1024，最小个数为2；（从 2.1.7.0 版本开始，改为最多允许 4096 列）
    2) 列名最大长度为64。
@@ -713,21 +713,49 @@ Query OK, 1 row(s) in set (0.001091s)
 | <=              | smaller than or equal to      | **`timestamp`** and all numeric types     |
 | =               | equal to                      | all types                                 |
 | <>              | not equal to                  | all types                                 |
+| is [not] null   | is null or is not null        | all types                                 |
 | between and     | within a certain range        | **`timestamp`** and all numeric types     |
 | in              | match any value in a set      | all types except first column `timestamp` |
 | like            | match a wildcard string       | **`binary`** **`nchar`**                  |
-| %               | match with any char sequences | **`binary`** **`nchar`**                  |
-| _               | match with a single char      | **`binary`** **`nchar`**                  |
 1. <> 算子也可以写为 != ，请注意，这个算子不能用于数据表第一列的 timestamp 字段。
 2. like 算子使用通配符字符串进行匹配检查。
  * 在通配符字符串中：'%'（百分号）匹配 0 到任意个字符；'\_'（下划线）匹配单个任意字符。
+    * 如果希望匹配字符串中原本就带有的 \_（下划线）字符，那么可以在通配符字符串中写作 `\_`，也即加一个反斜线来进行转义。（从 2.2.0.0 版本开始支持）
  * 通配符字符串最长不能超过 20 字节。（从 2.1.6.1 版本开始，通配符字符串的长度放宽到了 100 字节，并可以通过 taos.cfg 中的 maxWildCardsLength 参数来配置这一长度限制。但不建议使用太长的通配符字符串，将有可能严重影响 LIKE 操作的执行性能。）
 3. 同时进行多个字段的范围过滤，需要使用关键词 AND 来连接不同的查询条件，暂不支持 OR 连接的不同列之间的查询过滤条件。
+  * 从 2.3.0.0 版本开始，已支持完整的同一列和/或不同列间的 AND/OR 运算。
 4. 针对单一字段的过滤，如果是时间过滤条件，则一条语句中只支持设定一个；但针对其他的（普通）列或标签列，则可以使用 `OR` 关键字进行组合条件的查询过滤。例如： `((value > 20 AND value < 30) OR (value < 12))`。
+  * 从 2.3.0.0 版本开始，允许使用多个时间过滤条件，但首列时间戳的过滤运算结果只能包含一个区间。
 5. 从 2.0.17.0 版本开始，条件过滤开始支持 BETWEEN AND 语法，例如 `WHERE col2 BETWEEN 1.5 AND 3.25` 表示查询条件为“1.5 ≤ col2 ≤ 3.25”。
 6. 从 2.1.4.0 版本开始，条件过滤开始支持 IN 算子，例如 `WHERE city IN ('Beijing', 'Shanghai')`。说明：BOOL 类型写作 `{true, false}` 或 `{0, 1}` 均可，但不能写作 0、1 之外的整数；FLOAT 和 DOUBLE 类型会受到浮点数精度影响，集合内的值在精度范围内认为和数据行的值完全相等才能匹配成功；TIMESTAMP 类型支持非主键的列。<!-- REPLACE_OPEN_TO_ENTERPRISE__IN_OPERATOR_AND_UNSIGNED_INTEGER -->
+<a class="anchor" id="nested"></a>
+### 嵌套查询
+“嵌套查询”又称为“子查询”，也即在一条 SQL 语句中，“内层查询”的计算结果可以作为“外层查询”的计算对象来使用。
+从 2.2.0.0 版本开始，TDengine 的查询引擎开始支持在 FROM 子句中使用非关联子查询（“非关联”的意思是，子查询不会用到父查询中的参数）。也即在普通 SELECT 语句的 tb_name_list 位置，用一个独立的 SELECT 语句来代替（这一 SELECT 语句被包含在英文圆括号内），于是完整的嵌套查询 SQL 语句形如：
+```mysql
+SELECT ... FROM (SELECT ... FROM ...) ...;
+```
+说明：
+1. 目前仅支持一层嵌套，也即不能在子查询中再嵌入子查询。
+2. 内层查询的返回结果将作为“虚拟表”供外层查询使用，此虚拟表可以使用 AS 语法做重命名，以便于外层查询中方便引用。
+3. 目前不能在“连续查询”功能中使用子查询。
+4. 在内层和外层查询中，都支持普通的表间/超级表间 JOIN。内层查询的计算结果也可以再参与数据子表的 JOIN 操作。
+5. 目前内层查询、外层查询均不支持 UNION 操作。
+6. 内层查询支持的功能特性与非嵌套的查询语句能力是一致的。
+  * 内层查询的 ORDER BY 子句一般没有意义，建议避免这样的写法以免无谓的资源消耗。
+7. 与非嵌套的查询语句相比，外层查询所能支持的功能特性存在如下限制：
+  * 计算函数部分：
+    1. 如果内层查询的结果数据未提供时间戳，那么计算过程依赖时间戳的函数在外层会无法正常工作。例如：TOP, BOTTOM, FIRST, LAST, DIFF。
+    2. 计算过程需要两遍扫描的函数，在外层查询中无法正常工作。例如：此类函数包括：STDDEV, PERCENTILE。
+  * 外层查询中不支持 IN 算子，但在内层中可以使用。
+  * 外层查询不支持 GROUP BY。
 <a class="anchor" id="union"></a>
 ### UNION ALL 操作符
@@ -1036,7 +1064,7 @@ TDengine支持针对数据的聚合查询。提供支持的聚合和选择函数
    ```mysql
    SELECT LAST(field_name) FROM { tb_name | stb_name } [WHERE clause];
    ```
-    功能说明：统计表/超级表中某列的值最后写入的非NULL值。
+    功能说明：统计表/超级表中某列的值最后写入的非 NULL 值。
    返回结果数据类型：同应用的字段。
@@ -1046,9 +1074,11 @@ TDengine支持针对数据的聚合查询。提供支持的聚合和选择函数
    说明：
-    1）如果要返回各个列的最后（时间戳最大）一个非NULL值，可以使用LAST(\*)；
+    1）如果要返回各个列的最后（时间戳最大）一个非 NULL 值，可以使用 LAST(\*)；
+    2）如果结果集中的某列全部为 NULL 值，则该列的返回结果也是 NULL；如果结果集中所有列全部为 NULL 值，则不返回结果。
-    2）如果结果集中的某列全部为NULL值，则该列的返回结果也是NULL；如果结果集中所有列全部为NULL值，则不返回结果。
+    3）在用于超级表时，时间戳完全一样且同为最大的数据行可能有多个，那么会从中随机返回一条，而并不保证多次运行所挑选的数据行必然一致。
    示例：
    ```mysql
@@ -1197,7 +1227,9 @@ TDengine支持针对数据的聚合查询。提供支持的聚合和选择函数
    适用于：**表、超级表**。
-    限制：LAST_ROW()不能与INTERVAL一起使用。
+    限制：LAST_ROW() 不能与 INTERVAL 一起使用。
+    说明：在用于超级表时，时间戳完全一样且同为最大的数据行可能有多个，那么会从中随机返回一条，而并不保证多次运行所挑选的数据行必然一致。
    示例：
    ```mysql
@@ -1220,27 +1252,36 @@ TDengine支持针对数据的聚合查询。提供支持的聚合和选择函数
    ```
    功能说明：返回表/超级表的指定时间截面、指定字段的记录。
-    返回结果数据类型：同应用的字段。
+    返回结果数据类型：同字段类型。
-    应用字段：所有字段。
+    应用字段：数值型字段。
    适用于：**表、超级表**。
-    说明：（从 2.0.15.0 版本开始新增此函数）INTERP 必须指定时间断面，如果该时间断面不存在直接对应的数据，那么会根据 FILL 参数的设定进行插值。其中，条件语句里面可以附带更多的筛选条件，例如标签、tbname。
+    说明：（从 2.0.15.0 版本开始新增此函数）INTERP 必须指定时间断面，如果该时间断面不存在直接对应的数据，那么会根据 FILL 参数的设定进行插值。此外，条件语句里面可附带筛选条件，例如标签、tbname。
+    INTERP 查询要求查询的时间区间必须位于数据集合（表）的所有记录的时间范围之内。如果给定的时间戳位于时间范围之外，即使有插值指令，仍然不返回结果。
    示例：
-    ```mysql
+    ```sql
-    taos> select interp(*) from meters where ts='2017-7-14 10:42:00.005' fill(prev);
+    taos> SELECT INTERP(*) FROM meters WHERE ts='2017-7-14 18:40:00.004';
-           interp(ts)        | interp(f1)  | interp(f2)  | interp(f3)  |
+           interp(ts)        |   interp(current)    | interp(voltage) |    interp(phase)     |
-    ====================================================================
+    ==========================================================================================
-     2017-07-14 10:42:00.005 |           5 |           9 |           6 |
+     2017-07-14 18:40:00.004 |              9.84020 |             216 |              0.32222 |
-    Query OK, 1 row(s) in set (0.002912s)
+    Query OK, 1 row(s) in set (0.002652s)
+    ```
+    如果给定的时间戳无对应的数据，在不指定插值生成策略的情况下，不会返回结果，如果指定了插值策略，会根据插值策略返回结果。
-    taos> select interp(*) from meters where tbname in ('t1') and ts='2017-7-14 10:42:00.005' fill(prev);
+    ```sql
-           interp(ts)        | interp(f1)  | interp(f2)  | interp(f3)  |
+    taos> SELECT INTERP(*) FROM meters WHERE tbname IN ('d636') AND ts='2017-7-14 18:40:00.005';
-    ====================================================================
+    Query OK, 0 row(s) in set (0.004022s)
-     2017-07-14 10:42:00.005 |           5 |           6 |           7 |
-    Query OK, 1 row(s) in set (0.002005s)
+    taos> SELECT INTERP(*) FROM meters WHERE tbname IN ('d636') AND ts='2017-7-14 18:40:00.005' FILL(PREV);;
+           interp(ts)        |   interp(current)    | interp(voltage) |    interp(phase)     |
+    ==========================================================================================
+     2017-07-14 18:40:00.005 |              9.88150 |             217 |              0.32500 |
+    Query OK, 1 row(s) in set (0.003056s)
    ```
 ### 计算函数
@@ -1417,23 +1458,25 @@ SELECT AVG(current), MAX(current), LEASTSQUARES(current, start_val, step_val), P
 - 数据库名最大长度为 32。
 - 表名最大长度为 192，每行数据最大长度 16k 个字符（注意：数据行内每个 BINARY/NCHAR 类型的列还会额外占用 2 个字节的存储位置）。
- 列名最大长度为 64，最多允许 1024 列，最少需要 2 列，第一列必须是时间戳。
+- 列名最大长度为 64，最多允许 1024 列，最少需要 2 列，第一列必须是时间戳。（从 2.1.7.0 版本开始，改为最多允许 4096 列）
 - 标签名最大长度为 64，最多允许 128 个，可以 1 个，一个表中标签值的总长度不超过 16k 个字符。
 - SQL 语句最大长度 65480 个字符，但可通过系统配置参数 maxSQLLength 修改，最长可配置为 1M。
- SELECT 语句的查询结果，最多允许返回 1024 列（语句中的函数调用可能也会占用一些列空间），超限时需要显式指定较少的返回数据列，以避免语句执行报错。
+- SELECT 语句的查询结果，最多允许返回 1024 列（语句中的函数调用可能也会占用一些列空间），超限时需要显式指定较少的返回数据列，以避免语句执行报错。（从 2.1.7.0 版本开始，改为最多允许 4096 列）
 - 库的数目，超级表的数目、表的数目，系统不做限制，仅受系统资源限制。
-##  TAOS SQL其他约定
+## TAOS SQL 其他约定
 **GROUP BY的限制**
-TAOS  SQL支持对标签、TBNAME进行GROUP BY操作，也支持普通列进行GROUP BY，前提是：仅限一列且该列的唯一值小于10万个。
+TAOS SQL 支持对标签、TBNAME 进行 GROUP BY 操作，也支持普通列进行 GROUP BY，前提是：仅限一列且该列的唯一值小于 10 万个。
+**JOIN 操作的限制**
-**JOIN操作的限制**
+TAOS SQL 支持表之间按主键时间戳来 join 两张表的列，暂不支持两个表之间聚合后的四则运算。
-TAOS SQL支持表之间按主键时间戳来join两张表的列，暂不支持两个表之间聚合后的四则运算。
+JOIN 查询的不同表的过滤条件之间不能为 OR。
-**IS NOT NULL与不为空的表达式适用范围**
+**IS NOT NULL 与不为空的表达式适用范围**
-IS NOT NULL支持所有类型的列。不为空的表达式为 <>""，仅对非数值类型的列适用。
+IS NOT NULL 支持所有类型的列。不为空的表达式为 <>""，仅对非数值类型的列适用。
--- a/documentation20/cn/13.faq/docs.md
+++ b/documentation20/cn/13.faq/docs.md
@@ -98,7 +98,7 @@ TDengine 目前尚不支持删除功能，未来根据用户需求可能会支
 ## 10. 我怎么创建超过1024列的表？
-使用2.0及其以上版本，默认支持1024列；2.0之前的版本，TDengine最大允许创建250列的表。但是如果确实超过限值，建议按照数据特性，逻辑地将这个宽表分解成几个小表。
+使用 2.0 及其以上版本，默认支持 1024 列；2.0 之前的版本，TDengine 最大允许创建 250 列的表。但是如果确实超过限值，建议按照数据特性，逻辑地将这个宽表分解成几个小表。（从 2.1.7.0 版本开始，表的最大列数增加到了 4096 列。）
 ## 11. 最有效的写入数据的方法是什么？

--- a/documentation20/en/00.index/docs.md
+++ b/documentation20/en/00.index/docs.md
 # TDengine Documentation
-TDengine is a highly efficient platform to store, query, and analyze time-series data. It is specially designed and optimized for IoT, Internet of Vehicles, Industrial IoT, IT Infrastructure and Application Monitoring, etc. It works like a relational database, such as MySQL, but you are strongly encouraged to read through the following documentation before you experience it, especially the Data Model and Data Modeling sections. In addition to this document, you should also download and read our technology white paper. For the older TDengine version 1.6 documentation, please click here.
+TDengine is a highly efficient platform to store, query, and analyze time-series data. It is specially designed and optimized for IoT, Internet of Vehicles, Industrial IoT, IT Infrastructure and Application Monitoring, etc. It works like a relational database, such as MySQL, but you are strongly encouraged to read through the following documentation before you experience it, especially the Data Modeling sections. In addition to this document, you should also download and read the technology white paper. For the older TDengine version 1.6 documentation, please click [here](https://www.taosdata.com/en/documentation16/).
 ## [TDengine Introduction](/evaluation)
 * [TDengine Introduction and Features](/evaluation#intro)
 * [TDengine Use Scenes](/evaluation#scenes)
-* [TDengine Performance Metrics and Verification]((/evaluation#))
+* [TDengine Performance Metrics and Verification](/evaluation#)
 ## [Getting Started](/getting-started)
-* [Quickly Install](/getting-started#install): install via source code/package / Docker within seconds
+* [Quick Install](/getting-started#install): install via source code/package / Docker within seconds
+* [Quick Launch](/getting-started#start): start / stop TDengine quickly with systemctl
- [Easy to Launch](/getting-started#start): start / stop TDengine with systemctl
+* [Command-line](/getting-started#console) : an easy way to access TDengine server
- [Command-line](/getting-started#console) : an easy way to access TDengine server
+* [Experience Lightning Speed](/getting-started#demo): running a demo, inserting/querying data to experience faster speed
- [Experience Lightning Speed](/getting-started#demo): running a demo, inserting/querying data to experience faster speed
+* [List of Supported Platforms](/getting-started#platforms): a list of platforms supported by TDengine server and client
- [List of Supported Platforms](/getting-started#platforms): a list of platforms supported by TDengine server and client
+* [Deploy to Kubernetes](https://taosdata.github.io/TDengine-Operator/en/index.html)：a detailed guide for TDengine deployment in Kubernetes environment
- [Deploy to Kubernetes](https://taosdata.github.io/TDengine-Operator/en/index.html)：a detailed guide for TDengine deployment in Kubernetes environment
 ## [Overall Architecture](/architecture)
- [Data Model](/architecture#model): relational database model, but one table for one device with static tags
+- [Data Model](/architecture#model): relational database model, but one table for one data collection point with static tags
- [Cluster and Primary Logical Unit](/architecture#cluster): Take advantage of NoSQL, support scale-out and high-reliability
+- [Cluster and Primary Logical Unit](/architecture#cluster): Take advantage of NoSQL architecture, high availability and horizontal scalability
- [Storage Model and Data Partitioning/Sharding](/architecture#sharding): tag data will be separated from time-series data, segmented by vnode and time
+- [Storage Model and Data Partitioning/Sharding](/architecture#sharding): tag data is separated from time-series data, sharded by vnodes and partitioned by time 
- [Data Writing and Replication Process](/architecture#replication): records received are written to WAL, cached, with acknowledgement is sent back to client, while supporting multi-replicas
+- [Data Writing and Replication Process](/architecture#replication): records received are written to WAL, cached, with acknowledgement sent back to client, while supporting data replications
 - [Caching and Persistence](/architecture#persistence): latest records are cached in memory, but are written in columnar format with an ultra-high compression ratio
- [Data Query](/architecture#query): support various functions, time-axis aggregation, interpolation, and multi-table aggregation
+- [Data Query](/architecture#query): support various SQL functions, downsampling, interpolation, and multi-table aggregation
 ## [Data Modeling](/model)
- [Create a Database](/model#create-db): create a database for all data collection points with similar features
+- [Create a Database](/model#create-db): create a database for all data collection points with similar data characteristics
 - [Create a Super Table(STable)](/model#create-stable): create a STable for all data collection points with the same type
- [Create a Table](/model#create-table): use STable as the template, to create a table for each data collecting point
+- [Create a Table](/model#create-table): use STable as the template to create a table for each data collecting point
+## [Efficient Data Ingestion](/insert)
+- [Data Writing via SQL](/insert#sql): write one or multiple records into one or multiple tables via SQL insert command
+- [Data Writing via Prometheus](/insert#prometheus): Configure Prometheus to write data directly without any code
+- [Data Writing via Telegraf](/insert#telegraf): Configure Telegraf to write collected data directly without any code
+- [Data Writing via EMQ X](/insert#emq): Configure EMQ X to write MQTT data directly without any code
+- [Data Writing via HiveMQ Broker](/insert#hivemq): Configure HiveMQ to write MQTT data directly without any code
+## [Efficient Data Querying](/queries)
+- [Major Features](/queries#queries): support various standard query functions, setting filter conditions, and querying per time segment
+- [Multi-table Aggregation](/queries#aggregation): use STable and set tag filter conditions to perform efficient aggregation
+- [Downsampling](/queries#sampling): aggregate data in successive time windows, support interpolation
 ## [TAOS SQL](/taos-sql)
@@ -40,27 +53,13 @@ TDengine is a highly efficient platform to store, query, and analyze time-series
 - [Table Management](/taos-sql#table): add, drop, check, alter tables
 - [STable Management](/taos-sql#super-table): add, drop, check, alter STables
 - [Tag Management](/taos-sql#tags): add, drop, alter tags
- [Inserting Records](/taos-sql#insert): support to write single/multiple items per table, multiple items across tables, and support to write historical data
+- [Inserting Records](/taos-sql#insert): write single/multiple records a table, multiple records across tables, and historical data
 - [Data Query](/taos-sql#select): support time segment, value filtering, sorting, manual paging of query results, etc
 - [SQL Function](/taos-sql#functions): support various aggregation functions, selection functions, and calculation functions, such as avg, min, diff, etc
- [Time Dimensions Aggregation](/taos-sql#aggregation): aggregate and reduce the dimension after cutting table data by time segment
+- [Cutting and Aggregation](/taos-sql#aggregation): aggregate and reduce the dimension after cutting table data by time segment
 - [Boundary Restrictions](/taos-sql#limitation): restrictions for the library, table, SQL, and others
 - [Error Code](/taos-sql/error-code): TDengine 2.0 error codes and corresponding decimal codes
-## [Efficient Data Ingestion](/insert)
- [SQL Ingestion](/insert#sql): write one or multiple records into one or multiple tables via SQL insert command
- [Prometheus Ingestion](/insert#prometheus): Configure Prometheus to write data directly without any code
- [Telegraf Ingestion](/insert#telegraf): Configure Telegraf to write collected data directly without any code
- [EMQ X Broker](/insert#emq): Configure EMQ X to write MQTT data directly without any code
- [HiveMQ Broker](/insert#hivemq): Configure HiveMQ to write MQTT data directly without any code
-## [Efficient Data Querying](/queries)
- [Main Query Features](/queries#queries): support various standard functions, setting filter conditions, and querying per time segment
- [Multi-table Aggregation Query](/queries#aggregation): use STable and set tag filter conditions to perform efficient aggregation queries
- [Downsampling to Query Value](/queries#sampling): aggregate data in successive time windows, support interpolation
 ## [Advanced Features](/advanced-features)
 - [Continuous Query](/advanced-features#continuous-query): Based on sliding windows, the data stream is automatically queried and calculated at regular intervals
@@ -88,12 +87,12 @@ TDengine is a highly efficient platform to store, query, and analyze time-series
 ## [Installation and Management of TDengine Cluster](/cluster)
- [Preparation](/cluster#prepare): important considerations before deploying TDengine for production usage
+- [Preparation](/cluster#prepare): important steps before deploying TDengine for production usage
- [Create Your First Node](/cluster#node-one): simple to follow the quick setup
+- [Create the First Node](/cluster#node-one): just follow the steps in quick start 
 - [Create Subsequent Nodes](/cluster#node-other): configure taos.cfg for new nodes to add more to the existing cluster
 - [Node Management](/cluster#management): add, delete, and check nodes in the cluster
- [High-availability of Vnode](/cluster#high-availability): implement high-availability of Vnode through multi-replicas
+- [High-availability of Vnode](/cluster#high-availability): implement high-availability of Vnode through replicas
- [Mnode Management](/cluster#mnode): automatic system creation without any manual intervention
+- [Mnode Management](/cluster#mnode): mnodes are created automatically without any manual intervention
 - [Load Balancing](/cluster#load-balancing): automatically performed once the number of nodes or load changes
 - [Offline Node Processing](/cluster#offline): any node that offline for more than a certain period will be removed from the cluster
 - [Arbitrator](/cluster#arbitrator): used in the case of an even number of replicas to prevent split-brain
@@ -108,27 +107,14 @@ TDengine is a highly efficient platform to store, query, and analyze time-series
 - [Export Data](/administrator#export): export data either from TDengine shell or from the taosdump tool
 - [System Monitor](/administrator#status): monitor the system connections, queries, streaming calculation, logs, and events
 - [File Directory Structure](/administrator#directories): directories where TDengine data files and configuration files located
- [Parameter Restrictions and Reserved Keywords](/administrator#keywords): TDengine’s list of parameter restrictions and reserved keywords
+- [Parameter Limitss and Reserved Keywords](/administrator#keywords): TDengine’s list of parameter limits and reserved keywords
-## TDengine Technical Design
- [System Module]: taosd functions and modules partitioning
- [Data Replication]: support real-time synchronous/asynchronous replication, to ensure high-availability of the system
- [Technical Blog](https://www.taosdata.com/cn/blog/?categories=3): More technical analysis and architecture design articles
-## Common Tools
- [TDengine sample import tools](https://www.taosdata.com/blog/2020/01/18/1166.html)
- [TDengine performance comparison test tools](https://www.taosdata.com/blog/2020/01/18/1166.html)
- [Use TDengine visually through IDEA Database Management Tool](https://www.taosdata.com/blog/2020/08/27/1767.html)
 ## Performance: TDengine vs Others
- [Performance: TDengine vs InfluxDB with InfluxDB’s open-source performance testing tool](https://www.taosdata.com/blog/2020/01/13/1105.html)
+- [Performance: TDengine vs OpenTSDB](https://www.taosdata.com/blog/2019/09/12/710.html)
- [Performance: TDengine vs OpenTSDB](https://www.taosdata.com/blog/2019/08/21/621.html)
+- [Performance: TDengine vs Cassandra](https://www.taosdata.com/blog/2019/09/12/708.html)
- [Performance: TDengine vs Cassandra](https://www.taosdata.com/blog/2019/08/14/573.html)
+- [Performance: TDengine vs InfluxDB](https://www.taosdata.com/blog/2019/09/12/706.html)
- [Performance: TDengine vs InfluxDB](https://www.taosdata.com/blog/2019/07/19/419.html)
+- [Performance Test Reports of TDengine vs InfluxDB/OpenTSDB/Cassandra/MySQL/ClickHouse](https://www.taosdata.com/downloads/TDengine_Testing_Report_en.pdf)
- [Performance Test Reports of TDengine vs InfluxDB/OpenTSDB/Cassandra/MySQL/ClickHouse](https://www.taosdata.com/downloads/TDengine_Testing_Report_cn.pdf)
 ## More on IoT Big Data
@@ -136,7 +122,8 @@ TDengine is a highly efficient platform to store, query, and analyze time-series
 - [Features and Functions of IoT Big Data platforms](https://www.taosdata.com/blog/2019/07/29/542.html)
 - [Why don’t General Big Data Platforms Fit IoT Scenarios?](https://www.taosdata.com/blog/2019/07/09/why-does-the-general-big-data-platform-not-fit-iot-data-processing/)
 - [Why TDengine is the best choice for IoT, Internet of Vehicles, and Industry Internet Big Data platforms?](https://www.taosdata.com/blog/2019/07/09/why-tdengine-is-the-best-choice-for-iot-big-data-processing/)
+- [Technical Blog](https://www.taosdata.com/cn/blog/?categories=3): More technical analysis and architecture design articles
 ## FAQ
 - [FAQ: Common questions and answers](/faq)
\ No newline at end of file
--- a/documentation20/en/01.evaluation/docs.md
+++ b/documentation20/en/01.evaluation/docs.md
@@ -2,18 +2,18 @@
 ## <a class="anchor" id="intro"></a> About TDengine
-TDengine is an innovative Big Data processing product launched by Taos Data in the face of the fast-growing Internet of Things (IoT) Big Data market and technical challenges. It does not rely on any third-party software, nor does it optimize or package any open-source database or stream computing product. Instead, it is a product independently developed after absorbing the advantages of many traditional relational databases, NoSQL databases, stream computing engines, message queues, and other software. TDengine has its own unique Big Data processing advantages in time-series space.
+TDengine is an innovative Big Data processing product launched by TAOS Data in the face of the fast-growing Internet of Things (IoT) Big Data market and technical challenges. It does not rely on any third-party software, nor does it optimize or package any open-source database or stream computing product. Instead, it is a product independently developed after absorbing the advantages of many traditional relational databases, NoSQL databases, stream computing engines, message queues, and other software. TDengine has its own unique Big Data processing advantages in time-series space.
 One of the modules of TDengine is the time-series database. However, in addition to this,  to reduce the complexity of research and development and the difficulty of system operation, TDengine also provides functions such as caching, message queuing, subscription, stream computing, etc. TDengine provides a full-stack technical solution for the processing of IoT and Industrial Internet BigData. It is an efficient and easy-to-use IoT Big Data platform. Compared with typical Big Data platforms such as Hadoop, TDengine has the following distinct characteristics:
 - **Performance improvement over 10 times**: An innovative data storage structure is defined, with each single core can process at least 20,000 requests per second, insert millions of data points, and read more than 10 million data points, which is more than 10 times faster than other existing general database.
 - **Reduce the cost of hardware or cloud services to 1/5**: Due to its ultra-performance, TDengine’s computing resources consumption is less than 1/5 of other common Big Data solutions; through columnar storage and advanced compression algorithms, the storage consumption is less than 1/10 of other general databases.
 - **Full-stack time-series data processing engine**: Integrate database, message queue, cache, stream computing, and other functions, and the applications do not need to integrate with software such as Kafka/Redis/HBase/Spark/HDFS, thus greatly reducing the complexity cost of application development and maintenance.
- **Powerful analysis functions**: Data from ten years ago or one second ago, can all be queried based on a specified time range. Data can be aggregated on a timeline or multiple devices. Ad-hoc queries can be made at any time through Shell, Python, R, and MATLAB.
+- **Highly Available and Horizontal Scalable **: With the distributed architecture and consistency algorithm, via multi-replication and clustering features, TDengine ensures high availability and horizontal scalability to support the mission-critical applications.
- **Seamless connection with third-party tools**: Integration with Telegraf, Grafana, EMQ, HiveMQ, Prometheus, MATLAB, R, etc. without even one single line of code. OPC, Hadoop, Spark, etc. will be supported in the future, and more BI tools will be seamlessly connected to.
 - **Zero operation cost & zero learning cost**: Installing clusters is simple and quick, with real-time backup built-in, and no need to split libraries or tables. Similar to standard SQL, TDengine can support RESTful, Python/Java/C/C++/C#/Go/Node.js, and similar to MySQL with zero learning cost.
+- **Core is Open Sourced:** Except some auxiliary features, the core of TDengine is open sourced. Enterprise won't be locked by the database anymore. Ecosystem is more strong, product is more stable, and developer communities are more active. 
-With TDengine, the total cost of ownership of typical IoT, Internet of Vehicles, and Industrial Internet Big Data platforms can be greatly reduced. However, it should be pointed out that due to making full use of the characteristics of IoT time-series data, TDengine cannot be used to process general data from web crawlers, microblogs, WeChat, e-commerce, ERP, CRM, and other sources.
+With TDengine, the total cost of ownership of typical IoT, Internet of Vehicles, and Industrial Internet Big Data platforms can be greatly reduced. However, since it makes full use of the characteristics of IoT time-series data, TDengine cannot be used to process general data from web crawlers, microblogs, WeChat, e-commerce, ERP, CRM, and other sources.
 ![TDengine Technology Ecosystem](page://images/eco_system.png)
@@ -62,4 +62,4 @@ From the perspective of data sources, designers can analyze the applicability of
 | ------------------------------------------------- | ------------------ | ----------------------- | ------------------- | ------------------------------------------------------------ |
 | Require system with high-reliability         |                    |                      | √                   | TDengine has a very robust and reliable system architecture to implement simple and convenient daily operation with streamlined experiences for operators, thus human errors and accidents are eliminated to the greatest extent. |
 | Require controllable operation learning cost |                    |                      | √                   | As above.                                                    |
 | Require abundant talent supply               | √                  |                      |                     | As a new-generation product, it’s still difficult to find talents with TDengine experiences from market. However, the learning cost is low. As the vendor, we also provide extensive operation training and counselling services. |
\ No newline at end of file
--- a/documentation20/en/02.getting-started/01.docker/docs.md
+++ b/documentation20/en/02.getting-started/01.docker/docs.md
+# Quickly experience TDengine through Docker
+While it is not recommended to deploy TDengine services via Docker in a production environment, Docker tools do a good job of shielding the environmental differences in the underlying operating system and are well suited for use in development testing or first-time experience with the toolset for installing and running TDengine. In particular, Docker makes it relatively easy to try TDengine on Mac OSX and Windows systems without having to install a virtual machine or rent an additional Linux server. In addition, starting from version 2.0.14.0, TDengine provides images that support both X86-64, X86, arm64, and arm32 platforms, so non-mainstream computers that can run docker, such as NAS, Raspberry Pi, and embedded development boards, can also easily experience TDengine based on this document.
+The following article explains how to quickly build a single-node TDengine runtime environment via Docker to support development and testing through a Step by Step style introduction.
+## Docker download
+The Docker tools themselves can be downloaded from [Docker official site](https://docs.docker.com/get-docker/).
+After installation, you can check the Docker version in the command line terminal. If the version number is output properly, the Docker environment has been installed successfully.
+```bash
+$ docker -v
+Docker version 20.10.3, build 48d30b5
+```
+## Running TDengine in a Docker container
+1, Use the command to pull the TDengine image and make it run in the background.
+```bash
+$  docker run -d --name tdengine tdengine/tdengine
+7760c955f225d72e9c1ec5a4cef66149a7b94dae7598b11eb392138877e7d292
+```
+- **docker run**: Running a container via Docker
+- **--name tdengine**: Set the container name, we can see the corresponding container by the container name
+- **-d**: Keeping containers running in the background
+- **tdengine/tdengine**: Pulled from the official TDengine published application image
+- **7760c955f225d72e9c1ec5a4cef66149a7b94dae7598b11eb392138877e7d292**: The long character returned is the container ID, and we can also view the corresponding container by its container ID
+2, Verify that the container is running correctly.
+```bash
+$ docker ps
+CONTAINER ID   IMAGE               COMMAND   CREATED          STATUS          ···
+c452519b0f9b   tdengine/tdengine   "taosd"   14 minutes ago   Up 14 minutes   ···
+```
+- **docker ps**: Lists information about all containers that are in running state.
+- **CONTAINER ID**: Container ID.
+- **IMAGE**: The mirror used.
+- **COMMAND**: The command to run when starting the container.
+- **CREATED**: The time when the container was created.
+- **STATUS**: The container status. Up means running.
+3, Go inside the Docker container and use TDengine.
+```bash
+$ docker exec -it tdengine /bin/bash
+root@c452519b0f9b:~/TDengine-server-2.0.20.13# 
+```
+- **docker exec**: Enter the container via the docker exec command; if you exit, the container will not stop.
+- **-i**: Enter the interactive mode.
+- **-t**: Specify a terminal.
+- **c452519b0f9b**: The container ID, which needs to be modified according to the value returned by the docker ps command.
+- **/bin/bash**: Load the container and run bash to interact with it.
+4, After entering the container, execute the taos shell client program.
+```bash
+$ root@c452519b0f9b:~/TDengine-server-2.0.20.13# taos
+Welcome to the TDengine shell from Linux, Client Version:2.0.20.13
+Copyright (c) 2020 by TAOS Data, Inc. All rights reserved.
+taos> 
+```
+The TDengine terminal successfully connects to the server and prints out a welcome message and version information. If it fails, an error message is printed.
+In the TDengine terminal, you can create/delete databases, tables, super tables, etc., and perform insert and query operations via SQL commands. For details, you can refer to [TAOS SQL guide](https://www.taosdata.com/en/documentation/taos-sql).
+## Learn more about TDengine with taosdemo
+1, Following the above steps, exit the TDengine terminal program first.
+```bash
+$ taos> q
+root@c452519b0f9b:~/TDengine-server-2.0.20.13#
+```
+2, Execute taosdemo from the command line interface.
+```bash
+root@c452519b0f9b:~/TDengine-server-2.0.20.13# taosdemo
+taosdemo is simulating data generated by power equipments monitoring...
+host:                       127.0.0.1:6030
+user:                       root
+password:                   taosdata
+configDir:                  
+resultFile:                 ./output.txt
+thread num of insert data:  10
+thread num of create table: 10
+top insert interval:        0
+number of records per req:  30000
+max sql length:             1048576
+database count:             1
+database[0]:
+  database[0] name:      test
+  drop:                  yes
+  replica:               1
+  precision:             ms
+  super table count:     1
+  super table[0]:
+      stbName:           meters
+      autoCreateTable:   no
+      childTblExists:    no
+      childTblCount:     10000
+      childTblPrefix:    d
+      dataSource:        rand
+      iface:             taosc
+      insertRows:        10000
+      interlaceRows:     0
+      disorderRange:     1000
+      disorderRatio:     0
+      maxSqlLen:         1048576
+      timeStampStep:     1
+      startTimestamp:    2017-07-14 10:40:00.000
+      sampleFormat:      
+      sampleFile:        
+      tagsFile:          
+      columnCount:       3
+column[0]:FLOAT column[1]:INT column[2]:FLOAT 
+      tagCount:            2
+        tag[0]:INT tag[1]:BINARY(16) 
+         Press enter key to continue or Ctrl-C to stop
+```
+After enter, this command will automatically create a super table meters under the database test, there are 10,000 tables under this super table, the table name is "d0" to "d9999", each table has 10,000 records, each record has four fields (ts, current, voltage, phase), the time stamp is from "2017-07-14 10:40:00 000" to "2017-07-14 10:40:09 999", each table has a tag location and groupId, groupId is set from 1 to 10 and location is set to "beijing" or "shanghai".
+It takes about a few minutes to execute this command and ends up inserting a total of 100 million records.
+3, Go to the TDengine terminal and view the data generated by taosdemo.
+- **Go to the terminal interface.**
+```bash
+$ root@c452519b0f9b:~/TDengine-server-2.0.20.13# taos
+Welcome to the TDengine shell from Linux, Client Version:2.0.20.13
+Copyright (c) 2020 by TAOS Data, Inc. All rights reserved.
+taos> 
+```
+- **View the database.**
+```bash
+$ taos> show databases;
+  name        |      created_time       |   ntables   |   vgroups   |    ···
+  test        | 2021-08-18 06:01:11.021 |       10000 |           6 |    ···
+  log         | 2021-08-18 05:51:51.065 |           4 |           1 |	   ···
+```
+- **View Super Tables.**
+```bash
+$ taos> use test;
+Database changed.
+$ taos> show stables;
+              name              |      created_time       | columns |  tags  |   tables    |
+============================================================================================
+ meters                         | 2021-08-18 06:01:11.116 |       4 |      2 |       10000 |
+Query OK, 1 row(s) in set (0.003259s)
+```
+- **View the table and limit the output to 10 entries.**
+```bash
+$ taos> select * from test.t0 limit 10;
+DB error: Table does not exist (0.002857s)
+taos> select * from test.d0 limit 10;
+           ts            |       current        |   voltage   |        phase         |
+======================================================================================
+ 2017-07-14 10:40:00.000 |             10.12072 |         223 |              0.34167 |
+ 2017-07-14 10:40:00.001 |             10.16103 |         224 |              0.34445 |
+ 2017-07-14 10:40:00.002 |             10.00204 |         220 |              0.33334 |
+ 2017-07-14 10:40:00.003 |             10.00030 |         220 |              0.33333 |
+ 2017-07-14 10:40:00.004 |              9.84029 |         216 |              0.32222 |
+ 2017-07-14 10:40:00.005 |              9.88028 |         217 |              0.32500 |
+ 2017-07-14 10:40:00.006 |              9.88110 |         217 |              0.32500 |
+ 2017-07-14 10:40:00.007 |             10.08137 |         222 |              0.33889 |
+ 2017-07-14 10:40:00.008 |             10.12063 |         223 |              0.34167 |
+ 2017-07-14 10:40:00.009 |             10.16086 |         224 |              0.34445 |
+Query OK, 10 row(s) in set (0.016791s)
+```
+- **View the tag values for the d0 table.**
+```bash
+$ taos> select groupid, location from test.d0;
+   groupid   |     location     |
+=================================
+           0 | shanghai         |
+Query OK, 1 row(s) in set (0.003490s)
+```
+## Stop the TDengine service that is running in Docker
+```bash
+$ docker stop tdengine
+tdengine
+```
+- **docker stop**: Stop the specified running docker image with docker stop.
+- **tdengine**: The name of the container.
+## TDengine connected in Docker during programming development
+There are two ideas for connecting from outside of Docker to use TDengine services running inside a Docker container:
+1, By port mapping (-p), the open network port inside the container is mapped to the specified port of the host. By mounting the local directory (-v), you can synchronize the data inside the host and the container to prevent data loss after the container is deleted.
+```bash
+$ docker run -d -v /etc/taos:/etc/taos -P 6041:6041 tdengine/tdengine
+526aa188da767ae94b244226a2b2eec2b5f17dd8eff592893d9ec0cd0f3a1ccd
+$ curl -u root:taosdata -d 'show databases' 127.0.0.1:6041/rest/sql
+{"status":"succ","head":["name","created_time","ntables","vgroups","replica","quorum","days","keep0,keep1,keep(D)","cache(MB)","blocks","minrows","maxrows","wallevel","fsync","comp","cachelast","precision","update","status"],"column_meta":[["name",8,32],["created_time",9,8],["ntables",4,4],["vgroups",4,4],["replica",3,2],["quorum",3,2],["days",3,2],["keep0,keep1,keep(D)",8,24],["cache(MB)",4,4],["blocks",4,4],["minrows",4,4],["maxrows",4,4],["wallevel",2,1],["fsync",4,4],["comp",2,1],["cachelast",2,1],["precision",8,3],["update",2,1],["status",8,10]],"data":[["test","2021-08-18 06:01:11.021",10000,4,1,1,10,"3650,3650,3650",16,6,100,4096,1,3000,2,0,"ms",0,"ready"],["log","2021-08-18 05:51:51.065",4,1,1,1,10,"30,30,30",1,3,100,4096,1,3000,2,0,"us",0,"ready"]],"rows":2}
+```
+- The first command starts a docker container with TDengine running and maps the 6041 port of the container to port 6041 of the host.
+- The second command, accessing TDengine through the RESTful interface, connects to port 6041 on the local machine, so the connection is successful.
+Note: In this example, for convenience reasons, only port 6041 is mapped, which is required for RESTful. If you wish to connect to the TDengine service in a non-RESTful manner, you will need to map a total of 11 ports starting at 6030. In the example, mounting the local directory also only deals with the /etc/taos directory where the configuration files are located, but not the data storage directory.
+2, Go directly to the docker container to do development via the exec command. That is, put the program code in the same Docker container where the TDengine server is located and connect to the TDengine service local to the container.
+```bash
+$ docker exec -it tdengine /bin/bash
+```
--- a/documentation20/en/02.getting-started/docs.md
+++ b/documentation20/en/02.getting-started/docs.md
@@ -10,11 +10,13 @@ Please visit our [TDengine github page](https://github.com/taosdata/TDengine) fo
 ### Install from Docker Container
-Please visit our [TDengine Official Docker Image: Distribution, Downloading, and Usage](https://www.taosdata.com/blog/2020/05/13/1509.html).
+For the time being, it is not recommended to use Docker to deploy the client or server side of TDengine in production environments, but it is convenient to use Docker to deploy in development environments or when trying it for the first time. In particular, with Docker, it is easy to try TDengine in Mac OS X and Windows environments.
+Please refer to the detailed operation in [Quickly experience TDengine through Docker](https://www.taosdata.com/en/documentation/getting-started/docker).
 ### <a class="anchor" id="package-install"></a>Install from Package
-It’s extremely easy to install for TDengine, which takes only a few seconds from downloaded to successful installed. The server installation package includes clients and connectors. We provide 3 installation packages, which you can choose according to actual needs:
+Three different packages for TDengine server are provided, please pick up the one you like. (Lite packages only have execution files and connector of C/C++, but standard packages support connectors of nearly all programming languages.) Beta version has more features, but we suggest you to install stable version for production or testing.
 Click [here](https://www.taosdata.com/en/getting-started/#Install-from-Package) to download the install package.
@@ -129,7 +131,7 @@ After starting the TDengine server, you can execute the command `taosdemo` in th
 $ taosdemo
 ```
-Using this command, a STable named `meters` will be created in the database `test` There are 10k tables under this stable, named from `t0` to `t9999`. In each table there are 100k rows of records, each row with columns （`f1`, `f2` and `f3`. The timestamp is from "2017-07-14 10:40:00 000" to "2017-07-14 10:41:39 999". Each table also has tags `areaid` and `loc`: `areaid` is set from 1 to 10, `loc` is set to "beijing" or "shanghai".
+Using this command, a STable named `meters` will be created in the database `test`. There are 10k tables under this STable, named from `t0` to `t9999`. In each table there are 100k rows of records, each row with columns （`f1`, `f2` and `f3`. The timestamp is from "2017-07-14 10:40:00 000" to "2017-07-14 10:41:39 999". Each table also has tags `areaid` and `loc`: `areaid` is set from 1 to 10, `loc` is set to "beijing" or "shanghai".
 It takes about 10 minutes to execute this command. Once finished, 1 billion rows of records will be inserted.
@@ -199,7 +201,7 @@ Note: ● has been verified by official tests; ○ has been verified by unoffici
 List of platforms supported by TDengine client and connectors
-At the moment, TDengine connectors can support a wide range of platforms, including hardware platforms such as X64/X86/ARM64/ARM32/MIPS/Alpha, and development environments such as Linux/Win64/Win32.
+At the moment, TDengine connectors can support a wide range of platforms, including hardware platforms such as X64/X86/ARM64/ARM32/MIPS/Alpha, and operating system such as Linux/Win64/Win32.
 Comparison matrix as following:
@@ -216,4 +218,4 @@ Comparison matrix as following:
 Note: ● has been verified by official tests; ○ has been verified by unofficial tests.
-Please visit [Connectors](https://www.taosdata.com/en/documentation/connector) section for more detailed information.
+Please visit Connectors section for more detailed information.
\ No newline at end of file
--- a/documentation20/en/03.architecture/docs.md
+++ b/documentation20/en/03.architecture/docs.md
--- a/documentation20/en/04.model/docs.md
+++ b/documentation20/en/04.model/docs.md
@@ -2,17 +2,15 @@
 TDengine adopts a relational data model, so we need to build the "database" and "table". Therefore, for a specific application scenario, it is necessary to consider the design of the database, STable and ordinary table. This section does not discuss detailed syntax rules, but only concepts.
-Please watch the [video tutorial](https://www.taosdata.com/blog/2020/11/11/1945.html) for data modeling.
 ## <a class="anchor" id="create-db"></a> Create a Database
-Different types of data collection points often have different data characteristics, including frequency of data collecting, length of data retention time, number of replicas, size of data blocks, whether to update data or not, and so on. To ensure TDengine working with great efficiency in various scenarios, TDengine suggests creating tables with different data characteristics in different databases, because each database can be configured with different storage strategies. When creating a database, in addition to SQL standard options, the application can also specify a variety of parameters such as retention duration, number of replicas, number of memory blocks, time accuracy, max and min number of records in a file block, whether it is compressed or not, and number of days a data file will be overwritten. For example:
+Different types of data collection points often have different data characteristics, including data sampling rate, length of data retention time, number of replicas, size of data blocks, whether to update data or not, and so on. To ensure TDengine working with great efficiency in various scenarios, TDengine suggests creating tables with different data characteristics in different databases, because each database can be configured with different storage strategies. When creating a database, in addition to SQL standard options, the application can also specify a variety of parameters such as retention duration, number of replicas, number of memory blocks, time resolution, max and min number of records in a file block, whether it is compressed or not, and number of days covered by a data file. For example:
 ```mysql
 CREATE DATABASE power KEEP 365 DAYS 10 BLOCKS 6 UPDATE 1;
 ```
-The above statement will create a database named “power”. The data of this database will be kept for 365 days (it will be automatically deleted 365 days later), one data file created per 10 days, and the number of memory blocks is 4 for data updating. For detailed syntax and parameters, please refer to [Data Management section of TAOS SQL](https://www.taosdata.com/en/documentation/taos-sql#management).
+The above statement will create a database named “power”. The data of this database will be kept for 365 days (data will be automatically deleted 365 days later), one data file will be created per 10 days, the number of memory blocks is 4, and data updating is allowed. For detailed syntax and parameters, please refer to [Data Management section of TAOS SQL](https://www.taosdata.com/en/documentation/taos-sql#management).
 After the database created, please use SQL command USE to switch to the new database, for example:
@@ -20,7 +18,7 @@ After the database created, please use SQL command USE to switch to the new data
 USE power;	
 ```
-Replace the database operating in the current connection with “power”, otherwise, before operating on a specific table, you need to use "database name. table name" to specify the name of database to use.
+Specify the database operating in the current connection with “power”, otherwise, before operating on a specific table, you need to use "database-name.table-name" to specify the name of database to use.
 **Note:**
@@ -37,11 +35,11 @@ CREATE STABLE meters (ts timestamp, current float, voltage int, phase float) TAG
 **Note:** The STABLE keyword in this instruction needs to be written as TABLE in versions before 2.0.15.
-Just like creating an ordinary table, you need to provide the table name (‘meters’ in the example) and the table structure Schema, that is, the definition of data columns. The first column must be a timestamp (‘ts’ in the example), the other columns are the physical metrics collected (current, volume, phase in the example), and the data types can be int, float, string, etc. In addition, you need to provide the schema of the tag (location, groupId in the example), and the data types of the tag can be int, float, string and so on. Static attributes of collection points can often be used as tags, such as geographic location of collection points, device model, device group ID, administrator ID, etc. The schema of the tag can be added, deleted and modified afterwards. Please refer to the [STable Management section of TAOS SQL](https://www.taosdata.com/cn/documentation/taos-sql#super-table) for specific definitions and details.
+Just like creating an ordinary table, you need to provide the table name (‘meters’ in the example) and the table structure Schema, that is, the definition of data columns. The first column must be a timestamp (‘ts’ in the example), the other columns are the physical metrics collected (current, volume, phase in the example), and the data types can be int, float, string, etc. In addition, you need to provide the schema of the tag (location, groupId in the example), and the data types of the tag can be int, float, string and so on. Static attributes of data collection points can often be used as tags, such as geographic location of collection points, device model, device group ID, administrator ID, etc. The schema of the tags can be added, deleted and modified afterwards. Please refer to the [STable Management section of TAOS SQL](https://www.taosdata.com/cn/documentation/taos-sql#super-table) for specific definitions and details.
-Each type of data collection point needs an established STable, so an IoT system often has multiple STables. For the power grid, we need to build a STable for smart meters, transformers, buses, switches, etc. For IoT, a device may have multiple data collection points (for example, a fan for wind-driven generator, some collection points capture parameters such as current and voltage, and some capture environmental parameters such as temperature, humidity and wind direction). In this case, multiple STables need to be established for corresponding types of devices. All collected physical metrics contained in one and the same STable must be collected at the same time (with a consistent timestamp).
+A STable must be created for each type of data collection point, so an IoT system often has multiple STables. For the power grid, we need to build a STable for smart meters, a STable for transformers, a STable for buses, a STable for switches, etc. For IoT, a device may have multiple data collection points (for example, a fan for wind-driven generator, one data collection point captures metrics such as current and voltage, and one data collection point captures environmental parameters such as temperature, humidity and wind direction). In this case, multiple STables need to be established for corresponding types of devices. All metrics contained in a STable must be collected at the same time (with the same timestamp).
-A STable allows up to 1024 columns. If the number of physical metrics collected at a collection point exceeds 1024, multiple STables need to be built to process them. A system can have multiple DBs, and a DB can have one or more STables.
+A STable allows up to 1024 columns. If the number of metrics collected at a data collection point exceeds 1024, multiple STables need to be built to process them. A system can have multiple DBs, and a DB can have one or more STables.
 ## <a class="anchor" id="create-table"></a> Create a Table
@@ -53,22 +51,23 @@ CREATE TABLE d1001 USING meters TAGS ("Beijing.Chaoyang", 2);
 Where d1001 is the table name, meters is the name of the STable, followed by the specific tag value of tag Location as "Beijing.Chaoyang", and the specific tag value of tag groupId 2. Although the tag value needs to be specified when creating the table, it can be modified afterwards. Please refer to the [Table Management section of TAOS SQL](https://www.taosdata.com/en/documentation/taos-sql#table) for details.
-**Note: ** At present, TDengine does not technically restrict the use of a STable of a database (dbA) as a template to create a sub-table of another database (dbB). This usage will be prohibited later, and it is not recommended to use this method to create a table.
+**Note: ** At present, TDengine does not technically restrict the use of a STable of a database (dbA) as a template to create a sub-table of another database (dbB). This usage will be prohibited later, and it is not recommended to use this way to create a table.
 TDengine suggests to use the globally unique ID of data collection point as a table name (such as device serial number). However, in some scenarios, there is no unique ID, and multiple IDs can be combined into a unique ID. It is not recommended to use a unique ID as tag value.
-**Automatic table creating** : In some special scenarios, user is not sure whether the table of a certain data collection point exists when writing data. In this case, the non-existent table can be created by using automatic table building syntax when writing data. If the table already exists, no new table will be created. For example:
+**Automatic table creating** : In some special scenarios, user is not sure whether the table of a certain data collection point exists when writing data. In this case, the non-existent table can be created by using automatic table creating syntax when writing data. If the table already exists, no new table will be created. For example:
 ```mysql
 INSERT INTO d1001 USING METERS TAGS ("Beijng.Chaoyang", 2) VALUES (now, 10.2, 219, 0.32);
 ```
-The SQL statement above inserts records (now, 10.2, 219, 0.32) into table d1001. If table d1001 has not been created yet, the STable meters is used as the template to automatically create it, and the tag value "Beijing.Chaoyang", 2 is marked at the same time.
+The SQL statement above inserts records (now, 10.2, 219, 0.32) into table d1001. If table d1001 has not been created yet, the STable meters is used as the template to create it automatically, and the tag value "Beijing.Chaoyang", 2 is set at the same time.
 For detailed syntax of automatic table building, please refer to the "[Automatic Table Creation When Inserting Records](https://www.taosdata.com/en/documentation/taos-sql#auto_create_table)" section.
 ## Multi-column Model vs Single-column Model
-TDengine supports multi-column model. As long as physical metrics are collected simultaneously by a data collection point (with a consistent timestamp), these metrics can be placed in a STable as different columns. However, there is also an extreme design, a single-column model, in which each collected physical metric is set up separately, so each type of physical metrics is set up separately with a STable. For example, create 3 Stables, one each for current, voltage and phase.
+TDengine supports multi-column model. As long as metrics are collected simultaneously by a data collection point (with the same timestamp), these metrics can be placed in a STable as different columns. However, there is also an extreme design, a single-column model, in which a STable is created for each metric. For smart meter example, we need to create 3 Stables, one for current, one for voltage and one for phase.
+TDengine recommends using multi-column model as much as possible because of higher insertion and storage efficiency. However, for some scenarios, types of collected metrics often change. In this case, if multi-column model is adopted, the schema definition of STable needs to be modified frequently and the application becomes complicated. To avoid that, single-column model is recommended.
-TDengine recommends using multi-column model as much as possible because of higher insertion and storage efficiency. However, for some scenarios, types of collected metrics often change. In this case, if multi-column model is adopted, the structure definition of STable needs to be frequently modified so make the application complicated. To avoid that, single-column model is recommended.
--- a/documentation20/en/05.insert/docs.md
+++ b/documentation20/en/05.insert/docs.md
 # Efficient Data Writing
-TDengine supports multiple interfaces to write data, including SQL, Prometheus, Telegraf, EMQ MQTT Broker, HiveMQ Broker, CSV file, etc. Kafka, OPC and other interfaces will be provided in the future. Data can be inserted in a single piece or in batches, data from one or multiple data collection points can be inserted at the same time. TDengine supports multi-thread insertion, nonsequential data insertion, and also historical data insertion.
+TDengine supports multiple ways to write data, including SQL, Prometheus, Telegraf, EMQ MQTT Broker, HiveMQ Broker, CSV file, etc. Kafka, OPC and other interfaces will be provided in the future. Data can be inserted in one single record or in batches, data from one or multiple data collection points can be inserted at the same time. TDengine supports multi-thread insertion, out-of-order data insertion, and also historical data insertion.
-## <a class="anchor" id="sql"></a> SQL Writing
+## <a class="anchor" id="sql"></a> Data Writing via SQL 
-Applications insert data by executing SQL insert statements through C/C++, JDBC, GO, or Python Connector, and users can manually enter SQL insert statements to insert data through TAOS Shell. For example, the following insert writes a record to table d1001:
+Applications insert data by executing SQL insert statements through C/C++, JDBC, GO, C#, or Python Connector, and users can manually enter SQL insert statements to insert data through TAOS Shell. For example, the following insert writes a record to table d1001:
 ```mysql
 INSERT INTO d1001 VALUES (1538548685000, 10.3, 219, 0.31);
 ```
-TDengine supports writing multiple records at a time. For example, the following command writes two records to table d1001:
+TDengine supports writing multiple records in a single statement. For example, the following command writes two records to table d1001:
 ```mysql
 INSERT INTO d1001 VALUES (1538548684000, 10.2, 220, 0.23) (1538548696650, 10.3, 218, 0.25);
 ```
-TDengine also supports writing data to multiple tables at a time. For example, the following command writes two records to d1001 and one record to d1002:
+TDengine also supports writing data to multiple tables in a single statement. For example, the following command writes two records to d1001 and one record to d1002:
 ```mysql
 INSERT INTO d1001 VALUES (1538548685000, 10.3, 219, 0.31) (1538548695000, 12.6, 218, 0.33) d1002 VALUES (1538548696800, 12.3, 221, 0.31);
@@ -26,22 +26,22 @@ For the SQL INSERT Grammar, please refer to  [Taos SQL insert](https://www.taosd
 **Tips:**
- To improve writing efficiency, batch writing is required. The more records written in a batch, the higher the insertion efficiency. However, a record cannot exceed 16K, and the total length of an SQL statement cannot exceed 64K (it can be configured by parameter maxSQLLength, and the maximum can be configured to 1M).
+- To improve writing efficiency, batch writing is required. The more records written in a batch, the higher the insertion efficiency. However, a record size cannot exceed 16K, and the total length of an SQL statement cannot exceed 64K (it can be configured by parameter maxSQLLength, and the maximum can be configured to 1M).
- TDengine supports multi-thread parallel writing. To further improve writing speed, a client needs to open more than 20 threads to write parallelly. However, after the number of threads reaches a certain threshold, it cannot be increased or even become decreased, because too much frequent thread switching brings extra overhead.
+- TDengine supports multi-thread parallel writing. To further improve writing speed, a client needs to open more than 20 threads to write parallelly. However, after the number of threads reaches a certain threshold, it cannot be increased or even become decreased, because too much thread switching brings extra overhead.
- For a same table, if the timestamp of a newly inserted record already exists, (no database was created using UPDATE 1) the new record will be discarded as default, that is, the timestamp must be unique in a table. If an application automatically generates records, it is very likely that the generated timestamps will be the same, so the number of records successfully inserted will be smaller than the number of records the application try to insert. If you use UPDATE 1 option when creating a database, inserting a new record with the same timestamp will overwrite the original record.
+- For the same table, if the timestamp of a newly inserted record already exists, the new record will be discarded as default (database option update = 0), that is, the timestamp must be unique in a table. If an application automatically generates records, it is very likely that the generated timestamps will be the same, so the number of records successfully inserted will be smaller than the number of records the application try to insert. If you use UPDATE 1 option when creating a database, inserting a new record with the same timestamp will overwrite the original record.
 - The timestamp of written data must be greater than the current time minus the time of configuration parameter keep. If keep is configured for 3650 days, data older than 3650 days cannot be written. The timestamp for writing data cannot be greater than the current time plus configuration parameter days. If days is configured to 2, data 2 days later than the current time cannot be written.
-## <a class="anchor" id="prometheus"></a> Direct Writing of Prometheus
+## <a class="anchor" id="prometheus"></a> Data Writing via Prometheus
 As a graduate project of Cloud Native Computing Foundation, [Prometheus](https://www.prometheus.io/) is widely used in the field of performance monitoring and K8S performance monitoring. TDengine provides a simple tool [Bailongma](https://github.com/taosdata/Bailongma), which only needs to be simply configured in Prometheus without any code, and can directly write the data collected by Prometheus into TDengine, then automatically create databases and related table entries in TDengine according to rules. Blog post [Use Docker Container to Quickly Build a Devops Monitoring Demo](https://www.taosdata.com/blog/2020/02/03/1189.html), which is an example of using bailongma to write Prometheus and Telegraf data into TDengine.
 ### Compile blm_prometheus From Source
-Users need to download the source code of [Bailongma](https://github.com/taosdata/Bailongma) from github, then compile and generate an executable file using Golang language compiler. Before you start compiling, you need to complete following prepares:
+Users need to download the source code of [Bailongma](https://github.com/taosdata/Bailongma) from github, then compile and generate an executable file using Golang language compiler. Before you start compiling, you need to prepare:
 - A server running Linux OS
 - Golang version 1.10 and higher installed
- An appropriated TDengine version. Because the client dynamic link library of TDengine is used, it is necessary to install the same version of TDengine as the server-side; for example, if the server version is TDengine 2.0. 0, ensure install the same version on the linux server where bailongma is located (can be on the same server as TDengine, or on a different server)
+- Since the client dynamic link library of TDengine is used, it is necessary to install the same version of TDengine as the server-side. For example, if the server version is TDengine 2.0. 0, ensure install the same version on the linux server where bailongma is located (can be on the same server as TDengine, or on a different server)
 Bailongma project has a folder, blm_prometheus, which holds the prometheus writing API. The compiling process is as follows:
@@ -134,7 +134,7 @@ The format of generated data by Prometheus is as follows:
 }
 ```
-Where apiserver_request_latencies_bucket is the name of the time-series data collected by prometheus, and the tag of the time-series data is in the following {}. blm_prometheus automatically creates a STable in TDengine with the name of the time series data, and converts the tag in {} into the tag value of TDengine, with Timestamp as the timestamp and value as the value of the time-series data. Therefore, in the client of TDEngine, you can check whether this data was successfully written through the following instruction.
+Where apiserver_request_latencies_bucket is the name of the time-series data collected by prometheus, and the tag of the time-series data is in the following {}. blm_prometheus automatically creates a STable in TDengine with the name of the time series data, and converts the tag in {} into the tag value of TDengine, with Timestamp as the timestamp and value as the value of the time-series data. Therefore, in the client of TDengine, you can check whether this data was successfully written through the following instruction.
 ```mysql
 use prometheus;
@@ -144,7 +144,7 @@ select * from apiserver_request_latencies_bucket;
-## <a class="anchor" id="telegraf"></a> Direct Writing of Telegraf
+## <a class="anchor" id="telegraf"></a> Data Writing via Telegraf
 [Telegraf](https://www.influxdata.com/time-series-platform/telegraf/) is a popular open source tool for IT operation data collection. TDengine provides a simple tool [Bailongma](https://github.com/taosdata/Bailongma), which only needs to be simply configured in Telegraf without any code, and can directly write the data collected by Telegraf into TDengine, then automatically create databases and related table entries in TDengine according to rules. Blog post [Use Docker Container to Quickly Build a Devops Monitoring Demo](https://www.taosdata.com/blog/2020/02/03/1189.html), which is an example of using bailongma to write Prometheus and Telegraf data into TDengine.
@@ -271,12 +271,12 @@ select * from cpu;
 MQTT is a popular data transmission protocol in the IoT. TDengine can easily access the data received by MQTT Broker and write it to TDengine.
-## <a class="anchor" id="emq"></a> Direct Writing of EMQ Broker
+## <a class="anchor" id="emq"></a> Data Writing via EMQ Broker
 [EMQ](https://github.com/emqx/emqx) is an open source MQTT Broker software, with no need of coding, only to use "rules" in EMQ Dashboard for simple configuration, and MQTT data can be directly written into TDengine. EMQ X supports storing data to the TDengine by sending it to a Web service, and also provides a native TDengine driver on Enterprise Edition for direct data store. Please refer to [EMQ official documents](https://docs.emqx.io/broker/latest/cn/rule/rule-example.html#%E4%BF%9D%E5%AD%98%E6%95%B0%E6%8D%AE%E5%88%B0-tdengine) for more details.
-## <a class="anchor" id="hivemq"></a> Direct Writing of HiveMQ Broker
+## <a class="anchor" id="hivemq"></a> Data Writing via HiveMQ Broker
 [HiveMQ](https://www.hivemq.com/) is an MQTT agent that provides Free Personal and Enterprise Edition versions. It is mainly used for enterprises, emerging machine-to-machine(M2M) communication and internal transmission to meet scalability, easy management and security features. HiveMQ provides an open source plug-in development kit. You can store data to TDengine via HiveMQ extension-TDengine. Refer to the [HiveMQ extension-TDengine documentation](https://github.com/huskar-t/hivemq-tdengine-extension/blob/b62a26ecc164a310104df57691691b237e091c89/README.md) for more details.
\ No newline at end of file
--- a/documentation20/en/06.queries/docs.md
+++ b/documentation20/en/06.queries/docs.md
@@ -28,7 +28,7 @@ For specific query syntax, please see the [Data Query section of TAOS SQL](https
 ## <a class="anchor" id="aggregation"></a> Multi-table Aggregation Query
-In an IoT scenario, there are often multiple data collection points in a same type. TDengine uses the concept of STable to describe a certain type of data collection point, and an ordinary table to describe a specific data collection point. At the same time, TDengine uses tags to describe the statical attributes of data collection points. A given data collection point has a specific tag value. By specifying the filters of tags, TDengine provides an efficient method to aggregate and query the sub-tables of STables (data collection points of a certain type). Aggregation functions and most operations on ordinary tables are applicable to STables, and the syntax is exactly the same.
+In an IoT scenario, there are often multiple data collection points in a same type. TDengine uses the concept of STable to describe a certain type of data collection point, and an ordinary table to describe a specific data collection point. At the same time, TDengine uses tags to describe the static attributes of data collection points. A given data collection point has a specific tag value. By specifying the filters of tags, TDengine provides an efficient method to aggregate and query the sub-tables of STables (data collection points of a certain type). Aggregation functions and most operations on ordinary tables are applicable to STables, and the syntax is exactly the same.
 **Example 1**: In TAOS Shell, look up the average voltages collected by all smart meters in Beijing and group them by location
@@ -55,7 +55,7 @@ TDengine only allows aggregation queries between tables belonging to a same STab
 ## <a class="anchor" id="sampling"></a> Down Sampling Query, Interpolation
-In a scenario of IoT, it is often necessary to aggregate the collected data by intervals through down sampling. TDengine provides a simple keyword interval, which makes query operations according to time windows extremely simple. For example, the current values collected by smart meter d1001 are summed every 10 seconds.
+In a scenario of IoT, it is often necessary to aggregate the collected data by intervals through down sampling. TDengine provides a simple keyword `interval`, which makes query operations according to time windows extremely simple. For example, the current values collected by smart meter d1001 are summed every 10 seconds.
 ```mysql
 taos> SELECT sum(current) FROM d1001 INTERVAL(10s);
@@ -94,6 +94,6 @@ taos> SELECT SUM(current) FROM meters INTERVAL(1s, 500a);
 Query OK, 5 row(s) in set (0.001521s)
 ```
-In a scenario of IoT, it is difficult to synchronize the time stamp of collected data at each point, but many analysis algorithms (such as FFT) need to align the collected data strictly at equal intervals of time. In many systems, it’s required to write their own programs to process, but the down sampling operation of TDengine can be easily solved. If there is no collected data in an interval, TDengine also provides interpolation calculation function.
+In IoT scenario, it is difficult to synchronize the time stamp of collected data at each point, but many analysis algorithms (such as FFT) need to align the collected data strictly at equal intervals of time. In many systems, it’s required to write their own programs to process, but the down sampling operation of TDengine can be used to solve the problem easily. If there is no collected data in an interval, TDengine also provides interpolation calculation function.
 For details of syntax rules, please refer to the [Time-dimension Aggregation section of TAOS SQL](https://www.taosdata.com/en/documentation/taos-sql#aggregation).
\ No newline at end of file
--- a/documentation20/en/07.advanced-features/docs.md
+++ b/documentation20/en/07.advanced-features/docs.md
@@ -9,8 +9,8 @@ Continuous query of TDengine adopts time-driven mode, which can be defined direc
 The continuous query provided by TDengine differs from the time window calculation in ordinary stream computing in the following ways:
 - Unlike the real-time feedback calculated results of stream computing, continuous query only starts calculation after the time window is closed. For example, if the time period is 1 day, the results of that day will only be generated after 23:59:59.
- If a history record is written to the time interval that has been calculated, the continuous query will not recalculate and will not push the results to the user again. For the mode of writing back to TDengine, the existing calculated results will not be updated.
+- If a history record is written to the time interval that has been calculated, the continuous query will not re-calculate and will not push the new results to the user again. 
- Using the mode of continuous query pushing results, the server does not cache the client's calculation status, nor does it provide Exactly-Once semantic guarantee. If the user's application side crashed, the continuous query pulled up again would only recalculate the latest complete time window from the time pulled up again. If writeback mode is used, TDengine can ensure the validity and continuity of data writeback.
+- TDengine server does not cache or save the client's status, nor does it provide Exactly-Once semantic guarantee. If the application crashes, the continuous query will be pull up again and starting time must be provided by the application. 
 ### How to use continuous query
@@ -29,7 +29,7 @@ We already know that the average voltage of these meters can be counted with one
 select avg(voltage) from meters interval(1m) sliding(30s);
 ```
-Every time this statement is executed, all data will be recalculated. If you need to execute every 30 seconds to incrementally calculate the data of the latest minute, you can improve the above statement as following, using a different `startTime` each time and executing it regularly:
+Every time this statement is executed, all data will be re-calculated. If you need to execute every 30 seconds to incrementally calculate the data of the latest minute, you can improve the above statement as following, using a different `startTime` each time and executing it regularly:
 ```sql
 select avg(voltage) from meters where ts > {startTime} interval(1m) sliding(30s);
@@ -65,7 +65,7 @@ It should be noted that now in the above example refers to the time when continu
 ### Manage the Continuous Query
-Users can view all continuous queries running in the system through the show streams command in the console, and can kill the corresponding continuous queries through the kill stream command. Subsequent versions will provide more finer-grained and convenient continuous query management commands.
+Users can view all continuous queries running in the system through the `show streams` command in the console, and can kill the corresponding continuous queries through the `kill stream` command. Subsequent versions will provide more finer-grained and convenient continuous query management commands.
 ## <a class="anchor" id="subscribe"></a> Publisher/Subscriber
@@ -101,7 +101,7 @@ Another method is to query the STable. In this way, no matter how many meters th
 select * from meters where ts > {last_timestamp} and current > 10;
 ```
-However, how to choose `last_timestamp` has become a new problem. Because, on the one hand, the time of data generation (the data timestamp) and the time of data storage are generally not the same, and sometimes the deviation is still very large; On the other hand, the time when the data of different meters arrive at TDengine will also vary. Therefore, if we use the timestamp of the data from the slowest meter as `last_timestamp` in the query, we may repeatedly read the data of other meters; If the timestamp of the fastest meter is used, the data of other meters may be missed.
+However, how to choose `last_timestamp` has become a new problem. Because, on the one hand, the time of data generation (the data timestamp) and the time of data writing are generally not the same, and sometimes the deviation is still very large; On the other hand, the time when the data of different meters arrive at TDengine will also vary. Therefore, if we use the timestamp of the data from the slowest meter as `last_timestamp` in the query, we may repeatedly read the data of other meters; If the timestamp of the fastest meter is used, the data of other meters may be missed.
 The subscription function of TDengine provides a thorough solution to the above problem.
@@ -357,4 +357,4 @@ This SQL statement will obtain the last recorded voltage value of all smart mete
 In scenarios of TDengine, alarm monitoring is a common requirement. Conceptually, it requires the program to filter out data that meet certain conditions from the data of the latest period of time, and calculate a result according to a defined formula based on these data. When the result meets certain conditions and lasts for a certain period of time, it will notify the user in some form.
 In order to meet the needs of users for alarm monitoring, TDengine provides this function in the form of an independent module. For its installation and use, please refer to the blog [How to Use TDengine for Alarm Monitoring](https://www.taosdata.com/blog/2020/04/14/1438.html).
\ No newline at end of file
--- a/documentation20/en/08.connector/docs.md
+++ b/documentation20/en/08.connector/docs.md
@@ -296,9 +296,7 @@ Asynchronous APIs have relatively high requirements for users, who can selective
 The asynchronous APIs of TDengine all use non-blocking calling mode. Applications can use multithreading to open multiple tables at the same time, and can query or insert to each open table at the same time. It should be pointed out that the **application client must ensure that the operation on the same table is completely serialized**, that is, when the insertion or query operation on the same table is not completed (when no result returned), the second insertion or query operation cannot be performed.
 <a class="anchor" id="stmt"></a>
 ### Parameter binding API
 In addition to calling `taos_query` directly for queries, TDengine also provides a Prepare API that supports parameter binding. Like MySQL, these APIs currently only support using question mark `?` to represent the parameters to be bound, as follows:
@@ -823,12 +821,12 @@ https://www.taosdata.com/blog/2020/11/02/1901.html
 The TDengine provides the GO driver taosSql. taosSql implements the GO language's built-in interface database/sql/driver. Users can access TDengine in the application by simply importing the package as follows, see https://github.com/taosdata/driver-go/blob/develop/taosSql/driver_test.go for details.
-Sample code for using the Go connector can be found in https://github.com/taosdata/TDengine/tree/develop/tests/examples/go and the [video tutorial](https://www.taosdata.com/blog/2020/11/11/1951.html).
+Sample code for using the Go connector can be found in https://github.com/taosdata/TDengine/tree/develop/tests/examples/go .
 ```Go
 import (
    "database/sql"
-    _ "github.com/taosdata/driver-go/taosSql"
+    _ "github.com/taosdata/driver-go/v2/taosSql"
 )
 ```
@@ -839,6 +837,8 @@ go env -w GO111MODULE=on
 go env -w GOPROXY=https://goproxy.io,direct  
 ```
+`taosSql` v2 completed refactoring of the v1 version and separated the built-in database operation interface `database/sql/driver` to the directory `taosSql`, and put other advanced functions such as subscription and stmt into the directory `af`.
 ### Common APIs
 - `sql.Open(DRIVER_NAME string, dataSourceName string) *DB`
@@ -937,7 +937,7 @@ After installing the TDengine client, the nodejsChecker.js program can verify wh
 Steps:
-1. Create a new installation verification directory, for example: ~/tdengine-test, copy the nodejsChecker.js source program on github. Download address: （https://github.com/taosdata/TDengine/tree/develop/tests/examples/nodejs/nodejsChecker.js）.
+1. Create a new installation verification directory, for example: `~/tdengine-test`, copy the nodejsChecker.js source program on github. Download address: （https://github.com/taosdata/TDengine/tree/develop/tests/examples/nodejs/nodejsChecker.js）.
 2. Execute the following command:

--- a/documentation20/en/09.connections/docs.md
+++ b/documentation20/en/09.connections/docs.md
@@ -2,7 +2,7 @@
 ## <a class="anchor" id="grafana"></a> Grafana
-TDengine can quickly integrate with [Grafana](https://www.grafana.com/), an open source data visualization system, to build a data monitoring and alarming system. The whole process does not require any code to write. The contents of the data table in TDengine can be visually showed on DashBoard.
+TDengine can be quickly integrated with [Grafana](https://www.grafana.com/), an open source data visualization system, to build a data monitoring and alarming system. The whole process does not require any code to write. The contents of the data table in TDengine can be visually showed on DashBoard.
 ### Install Grafana

--- a/documentation20/en/10.cluster/docs.md
+++ b/documentation20/en/10.cluster/docs.md
 # TDengine Cluster Management
-Multiple TDengine servers, that is, multiple running instances of taosd, can form a cluster to ensure the highly reliable operation of TDengine and provide scale-out features. To understand cluster management in TDengine 2.0, it is necessary to understand the basic concepts of clustering. Please refer to the chapter "Overall Architecture of TDengine 2.0". And before installing the cluster, please follow the chapter ["Getting started"](https://www.taosdata.com/en/documentation/getting-started/) to install and experience the single node function.
+Multiple TDengine servers, that is, multiple running instances of taosd, can form a cluster to ensure the highly reliable operation of TDengine and provide scale-out features. To understand cluster management in TDengine 2.0, it is necessary to understand the basic concepts of clustering. Please refer to the chapter "Overall Architecture of TDengine 2.0". And before installing the cluster, please follow the chapter ["Getting started"](https://www.taosdata.com/en/documentation/getting-started/) to install and experience the single node TDengine.
-Each data node of the cluster is uniquely identified by End Point, which is composed of FQDN (Fully Qualified Domain Name) plus Port, such as [h1.taosdata.com](http://h1.taosdata.com/):6030. The general FQDN is the hostname of the server, which can be obtained through the Linux command `hostname -f` (how to configure FQDN, please refer to: [All about FQDN of TDengine](https://www.taosdata.com/blog/2020/09/11/1824.html)). Port is the external service port number of this data node. The default is 6030, but it can be modified by configuring the parameter serverPort in taos.cfg. A physical node may be configured with multiple hostnames, and TDengine will automatically get the first one, but it can also be specified through the configuration parameter fqdn in taos.cfg. If you are accustomed to direct IP address access, you can set the parameter fqdn to the IP address of this node.
+Each data node of the cluster is uniquely identified by End Point, which is composed of FQDN (Fully Qualified Domain Name) plus Port, such as [h1.taosdata.com](http://h1.taosdata.com/):6030. The general FQDN is the hostname of the server, which can be obtained through the Linux command `hostname -f` (how to configure FQDN, please refer to: [All about FQDN of TDengine](https://www.taosdata.com/blog/2020/09/11/1824.html)). Port is the external service port number of this data node. The default is 6030, but it can be modified by configuring the parameter serverPort in taos.cfg. A physical node may be configured with multiple hostnames, and TDengine will automatically get the first one, but it can also be specified through the configuration parameter `fqdn` in taos.cfg. If you want to access via direct IP address, you can set the parameter `fqdn` to the IP address of this node.
 The cluster management of TDengine is extremely simple. Except for manual intervention in adding and deleting nodes, all other tasks are completed automatically, thus minimizing the workload of operation. This chapter describes the operations of cluster management in detail.
@@ -12,11 +12,11 @@ Please refer to the [video tutorial](https://www.taosdata.com/blog/2020/11/11/19
 **Step 0:** Plan FQDN of all physical nodes in the cluster, and add the planned FQDN to /etc/hostname of each physical node respectively; modify the /etc/hosts of each physical node, and add the corresponding IP and FQDN of all cluster physical nodes. [If DNS is deployed, contact your network administrator to configure it on DNS]
-**Step 1:** If the physical nodes have previous test data, installed with version 1. x, or installed with other versions of TDengine, please delete it first and drop all data. For specific steps, please refer to the blog "[Installation and Uninstallation of Various Packages of TDengine](https://www.taosdata.com/blog/2019/08/09/566.html)"
+**Step 1:** If the physical nodes have previous test data, installed with version 1. x, or installed with other versions of TDengine, please backup all data, then delete it and drop all data. For specific steps, please refer to the blog "[Installation and Uninstallation of Various Packages of TDengine](https://www.taosdata.com/blog/2019/08/09/566.html)"
 **Note 1:** Because the information of FQDN will be written into a file, if FQDN has not been configured or changed before, and TDengine has been started, be sure to clean up the previous data （`rm -rf /var/lib/taos/*`）on the premise of ensuring that the data is useless or backed up;
-**Note 2:** The client also needs to be configured to ensure that it can correctly parse the FQDN configuration of each node, whether through DNS service or Host file.
+**Note 2:** The client also needs to be configured to ensure that it can correctly parse the FQDN configuration of each node, whether through DNS service or modify hosts file.
 **Step 2:** It is recommended to close the firewall of all physical nodes, and at least ensure that the TCP and UDP ports of ports 6030-6042 are open. It is **strongly recommended** to close the firewall first and configure the ports after the cluster is built;
@@ -136,7 +136,7 @@ Execute the CLI program taos, log in to the TDengine system using the root accou
 DROP DNODE "fqdn:port";
 ```
-Where fqdn is the FQDN of the deleted node, and port is the port number of its external server.
+Where fqdn is the FQDN of the deleted node, and port is the port number.
 <font color=green>**【Note】**</font>
@@ -185,7 +185,7 @@ Because of the introduction of vnode, it is impossible to simply draw a conclusi
 TDengine cluster is managed by mnode (a module of taosd, management node). In order to ensure the high-availability of mnode, multiple mnode replicas can be configured. The number of replicas is determined by system configuration parameter numOfMnodes, and the effective range is 1-3. In order to ensure the strong consistency of metadata, mnode replicas are duplicated synchronously.
-A cluster has multiple data node dnodes, but a dnode runs at most one mnode instance. In the case of multiple dnodes, which dnode can be used as an mnode? This is automatically specified by the system according to the resource situation on the whole. User can execute the following command in the console of TDengine through the CLI program taos:
+A cluster has multiple data node dnodes, but a dnode runs at most one mnode instance. In the case of multiple dnodes, which dnode can be used as an mnode? This is automatically selected by the system based on the resource on the whole. User can execute the following command in the console of TDengine through the CLI program taos:
 ```
 SHOW MNODES;
@@ -213,7 +213,7 @@ When the above three situations occur, the system will start a load computing of
 If a data node is offline, the TDengine cluster will automatically detect it. There are two detailed situations:
- If the data node is offline for more than a certain period of time (configuration parameter offlineThreshold in taos.cfg controls the duration), the system will automatically delete the data node, generate system alarm information and trigger the load balancing process. If the deleted data node is online again, it will not be able to join the cluster, and the system administrator will need to add it to the cluster again.
+- If the data node is offline for more than a certain period of time (configuration parameter `offlineThreshold` in taos.cfg controls the duration), the system will automatically delete the data node, generate system alarm information and trigger the load balancing process. If the deleted data node is online again, it will not be able to join the cluster, and the system administrator will need to add it to the cluster again.
 - After offline, the system will automatically start the data recovery process if it goes online again within the duration of offlineThreshold. After the data is fully recovered, the node will start to work normally.
 **Note:** If each data node belonging to a virtual node group (including mnode group) is in offline or unsynced state, Master can only be elected after all data nodes in the virtual node group are online and can exchange status information, and the virtual node group can serve externally. For example, the whole cluster has 3 data nodes with 3 replicas. If all 3 data nodes go down and then 2 data nodes restart, it will not work. Only when all 3 data nodes restart successfully can serve externally again.
@@ -229,7 +229,7 @@ The name of the executable for Arbitrator is tarbitrator. The executable has alm
 1. Click [Package Download](https://www.taosdata.com/cn/all-downloads/), and in the TDengine Arbitrator Linux section, select the appropriate version to download and install.
-2. The command line parameter  -p of this application can specify the port number of its external service, and the default is 6042.
+2. The command line parameter  -p of this application can specify the port number of its service, and the default is 6042.
 3. Modify the configuration file of each taosd instance, and set parameter arbitrator to the End Point corresponding to the tarbitrator in taos.cfg. (If this parameter is configured, when the number of replicas is even, the system will automatically connect the configured Arbitrator. If the number of replicas is odd, even if the Arbitrator is configured, the system will not establish a connection.)
 4. The Arbitrator configured in the configuration file will appear in the return result of instruction `SHOW DNODES`; the value of the corresponding role column will be "arb".
--- a/documentation20/en/11.administrator/docs.md
+++ b/documentation20/en/11.administrator/docs.md
@@ -22,8 +22,8 @@ If there is plenty of memory, the configuration of Blocks can be increased so th
 CPU requirements depend on the following two aspects:
- **Data insertion** TDengine single core can handle at least 10,000 insertion requests per second. Each insertion request can take multiple records, and inserting one record at a time is almost the same as inserting 10 records in computing resources consuming. Therefore, the larger the number of inserts, the higher the insertion efficiency. If an insert request has more than 200 records, a single core can insert 1 million records per second. However, the faster the insertion speed, the higher the requirement for front-end data collection, because records need to be cached and then inserted in batches.
+- **Data insertion**: TDengine single core can handle at least 10,000 insertion requests per second. Each insertion request can take multiple records, and inserting one record at a time is almost the same as inserting 10 records in computing resources consuming. Therefore, the larger the number of records per insert, the higher the insertion efficiency. If an insert request has more than 200 records, a single core can insert 1 million records per second. However, the faster the insertion speed, the higher the requirement for front-end data collection, because records need to be cached and then inserted in batches.
- **Query requirements** TDengine to provide efficient queries, but the queries in each scenario vary greatly and the query frequency too, making it difficult to give objective figures. Users need to write some query statements for their own scenes to determine.
+- **Query**: TDengine provides efficient queries, but the queries in each scenario vary greatly and the query frequency too, making it difficult to give objective figures. Users need to write some query statements for their own scenes to estimate.
 Therefore, only for data insertion, CPU can be estimated, but the computing resources consumed by query cannot be that clear. In the actual operation, it is not recommended to make CPU utilization rate over 50%. After that, new nodes need to be added to bring more computing resources.
@@ -78,7 +78,7 @@ When the nodes in TDengine cluster are deployed on different physical machines a
 ## <a class="anchor" id="config"></a> Server-side Configuration
-The background service of TDengine system is provided by taosd, and the configuration parameters can be modified in the configuration file taos.cfg to meet the requirements of different scenarios. The default location of the configuration file is the /etc/taos directory, which can be specified by executing the parameter -c from the taosd command line. Such as taosd-c/home/user, to specify that the configuration file is located in the /home/user directory.
+The background service of TDengine system is provided by taosd, and the configuration parameters can be modified in the configuration file taos.cfg to meet the requirements of different scenarios. The default location of the configuration file is the /etc/taos directory, which can be specified by executing the parameter `-c` from the taosd command line. Such as `taosd -c /home/user`, to specify that the configuration file is located in the /home/user directory.
 You can also use “-C” to show the current server configuration parameters:
@@ -88,14 +88,14 @@ taosd -C
 Only some important configuration parameters are listed below. For more parameters, please refer to the instructions in the configuration file. Please refer to the previous chapters for detailed introduction and function of each parameter, and the default of these parameters is working and generally does not need to be set. **Note: After the configuration is modified, \*taosd service\* needs to be restarted to take effect.**
- firstEp: end point of the first dnode in the actively connected cluster when taosd starts, the default value is localhost: 6030.
+- firstEp: end point of the first dnode which will be connected in the cluster when taosd starts, the default value is localhost: 6030.
- fqdn: FQDN of the data node, which defaults to the first hostname configured by the operating system. If you are accustomed to IP address access, you can set it to the IP address of the node.
+- fqdn: FQDN of the data node, which defaults to the first hostname configured by the operating system. If you want to access via IP address directly, you can set it to the IP address of the node.
 - serverPort: the port number of the external service after taosd started, the default value is 6030.
 - httpPort: the port number used by the RESTful service to which all HTTP requests (TCP) require a query/write request. The default value is 6041.
 - dataDir: the data file directory to which all data files will be written. [Default:/var/lib/taos](http://default/var/lib/taos).
 - logDir: the log file directory to which the running log files of the client and server will be written. [Default:/var/log/taos](http://default/var/log/taos).
- arbitrator: the end point of the arbiter in the system; the default value is null.
+- arbitrator: the end point of the arbitrator in the system; the default value is null.
- role: optional role for dnode. 0-any; it can be used as an mnode and to allocate vnodes; 1-mgmt; It can only be an mnode, but not to allocate vnodes; 2-dnode; caannot be an mnode, only vnode can be allocated
+- role: optional role for dnode. 0-any; it can be used as an mnode and to allocate vnodes; 1-mgmt; It can only be an mnode, but not to allocate vnodes; 2-dnode; cannot be an mnode, only vnode can be allocated
 - debugFlage: run the log switch. 131 (output error and warning logs), 135 (output error, warning, and debug logs), 143 (output error, warning, debug, and trace logs). Default value: 131 or 135 (different modules have different default values).
 - numOfLogLines: the maximum number of lines allowed for a single log file. Default: 10,000,000 lines.
 - logKeepDays: the maximum retention time of the log file. When it is greater than 0, the log file will be renamed to taosdlog.xxx, where xxx is the timestamp of the last modification of the log file in seconds. Default: 0 days.
@@ -161,18 +161,18 @@ For example:
 ## <a class="anchor" id="client"></a> Client Configuration
-The foreground interactive client application of TDengine system is taos and application driver, which shares the same configuration file taos.cfg with taosd. When running taos, use the parameter -c to specify the configuration file directory, such as taos-c/home/cfg, which means using the parameters in the taos.cfg configuration file under the /home/cfg/ directory. The default directory is /etc/taos. For more information on how to use taos, see the help information taos --help. This section mainly describes the parameters used by the taos client application in the configuration file taos.cfg.
+The foreground interactive client application of TDengine system is taos and application driver, which shares the same configuration file taos.cfg with taosd. When running taos, use the parameter `-c` to specify the configuration file directory, such as `taos -c /home/cfg`, which means using the parameters in the taos.cfg configuration file under the /home/cfg/ directory. The default directory is /etc/taos. For more information on how to use taos, see the help information `taos --help`. This section mainly describes the parameters used by the taos client application in the configuration file taos.cfg.
 **Versions after 2.0. 10.0 support the following parameters on command line to display the current client configuration parameters**
 ```bash
-taos -C  或  taos --dump-config
+taos -C  or  taos --dump-config
 ```
 Client configuration parameters:
 - firstEp: end point of the first taosd instance in the actively connected cluster when taos is started, the default value is localhost: 6030.
- secondEp: when taos starts, if not impossible to connect to firstEp, it will try to connect to secondEp.
+- secondEp: when taos starts, if unable to connect to firstEp, it will try to connect to secondEp.
 - locale
    Default value: obtained dynamically from the system. If the automatic acquisition fails, user needs to set it in the configuration file or through API
@@ -493,4 +493,4 @@ At the moment, TDengine has nearly 200 internal reserved keywords, which cannot
 | CONCAT               | GLOB        | METRICS      | SET        | VIEW      |
 | CONFIGS              | GRANTS      | MIN          | SHOW       | WAVG      |
 | CONFLICT             | GROUP       | MINUS        | SLASH      | WHERE     |
 | CONNECTION           |             |              |            |           |
\ No newline at end of file
--- a/documentation20/en/12.taos-sql/docs.md
+++ b/documentation20/en/12.taos-sql/docs.md
 # TAOS SQL
-TDengine provides a SQL-style language, TAOS SQL, to insert or query data, and support other common tips. To finish this document, you should have some understanding about SQL.
+TDengine provides a SQL-style language, TAOS SQL, to insert or query data. To read through this document, you should have some basic understanding about SQL.
-TAOS SQL is the main tool for users to write and query data to TDengine. TAOS SQL provides a style and mode similar to standard SQL to facilitate users to get started quickly. Strictly speaking, TAOS SQL is not and does not attempt to provide SQL standard syntax. In addition, since TDengine does not provide deletion function for temporal structured data, the relevant function of data deletion is non-existent in TAO SQL.
+TAOS SQL is the main way for users to write and query data to TDengine. TAOS SQL is similar to standard SQL to facilitate users to get started quickly. Strictly speaking, TAOS SQL is not and does not attempt to provide SQL standard syntax. In addition, since TDengine does not provide deletion function for time-series data, the relevant function of data deletion is non-existent in TAO SQL.
 Let’s take a look at the conventions used for syntax descriptions.
@@ -127,7 +127,7 @@ Note:
    ALTER DATABASE db_name CACHELAST 0;
    ```
    CACHELAST parameter controls whether last_row of the data subtable is cached in memory. The default value is 0, and the value range is [0, 1]. Where 0 means not enabled and 1 means enabled. (supported from version 2.0. 11)
    **Tips**: After all the above parameters are modified, show databases can be used to confirm whether the modification is successful.
 - **Show all databases in system**
@@ -138,14 +138,17 @@ Note:
 ## <a class="anchor" id="table"></a> Table Management
- Create a table
+- **Create a table**
-Note:
-1. The first field must be a timestamp, and system will set it as the primary key;
+    ```mysql
-2. The max length of table name is 192;
+    CREATE TABLE [IF NOT EXISTS] tb_name (timestamp_field_name TIMESTAMP, field1_name data_type1 [, field2_name data_type2 ...]);
-3. The length of each row of the table cannot exceed 16k characters;
+    ```
-4. Sub-table names can only consist of letters, numbers, and underscores, and cannot begin with numbers
+  Note:
-5. If the data type binary or nchar is used, the maximum number of bytes should be specified, such as binary (20), which means 20 bytes;
+   1. The first field must be a timestamp, and system will set it as the primary key;
+   2. The max length of table name is 192;
+   3. The length of each row of the table cannot exceed 16k characters;
+   4. Sub-table names can only consist of letters, numbers, and underscores, and cannot begin with numbers
+   5. If the data type binary or nchar is used, the maximum number of bytes should be specified, such as binary (20), which means 20 bytes;
 - **Create a table via STable**
@@ -171,10 +174,10 @@ Note:
   Note:
   1. The method of batch creating tables requires that the data table must use STable as a template.
-   2. On the premise of not exceeding the length limit of SQL statements, it is suggested that the number of tables in a single statement should be controlled between 1000 and 3000, which will obtain an ideal speed of table building.
+   2. On the premise of not exceeding the length limit of SQL statements, it is suggested that the number of tables in a single statement should be controlled between 1000 and 3000, which will obtain an ideal speed of table creating.
 - **Drop a table**
    ```mysql
    DROP TABLE [IF EXISTS] tb_name;
    ```
@@ -218,7 +221,7 @@ Note:
 ## <a class="anchor" id="super-table"></a> STable Management
-Note: In 2.0. 15.0 and later versions, STABLE reserved words are supported. That is, in the instruction description later in this section, the three instructions of CREATE, DROP and ALTER need to write TABLE instead of STABLE in the old version as the reserved word.
+Note: In 2.0.15.0 and later versions, STABLE reserved words are supported. That is, in the instruction description later in this section, the three instructions of CREATE, DROP and ALTER need to write TABLE instead of STABLE in the old version as the reserved word.
 - **Create a STable**
@@ -290,7 +293,7 @@ Note: In 2.0. 15.0 and later versions, STABLE reserved words are supported. That
    Modify a tag name of STable. After modifying, all sub-tables under the STable will automatically update the new tag name.
 - **Modify a tag value of sub-table**
    ```mysql
    ALTER TABLE tb_name SET TAG tag_name=new_tag_value;
    ```
@@ -306,7 +309,7 @@ Note: In 2.0. 15.0 and later versions, STABLE reserved words are supported. That
  Insert a record into table tb_name.
 - **Insert a record with data corresponding to a given column**
    ```mysql
    INSERT INTO tb_name (field1_name, ...) VALUES (field1_value1, ...);
    ```
@@ -320,14 +323,14 @@ Note: In 2.0. 15.0 and later versions, STABLE reserved words are supported. That
    Insert multiple records into table tb_name.
 - **Insert multiple records into a given column**
    ```mysql
    INSERT INTO tb_name (field1_name, ...) VALUES (field1_value1, ...) (field1_value2, ...) ...;
    ```
    Insert multiple records into a given column of table tb_name.
 - **Insert multiple records into multiple tables**
    ```mysql
    INSERT INTO tb1_name VALUES (field1_value1, ...) (field1_value2, ...) ...
                tb2_name VALUES (field1_value1, ...) (field1_value2, ...) ...;
@@ -421,7 +424,7 @@ taos> SELECT * FROM d1001;
 Query OK, 3 row(s) in set (0.001165s)
 ```
-For Stables, wildcards contain *tag columns*.
+For STables, wildcards contain *tag columns*.
 ```mysql
 taos> SELECT * FROM meters;
@@ -720,7 +723,7 @@ TDengine supports aggregations over data, they are listed below:
    ================================================
                        9 |                     9 |
    Query OK, 1 row(s) in set (0.004475s)
    taos> SELECT COUNT(*), COUNT(voltage) FROM d1001;
        count(*)        |    count(voltage)     |
    ================================================
@@ -758,7 +761,7 @@ TDengine supports aggregations over data, they are listed below:
  ```
 - **TWA**
  ```mysql
  SELECT TWA(field_name) FROM tb_name WHERE clause;
  ```
@@ -799,7 +802,7 @@ TDengine supports aggregations over data, they are listed below:
  ================================================================================
              35.200000763 |                   658 |               0.950000018 |
  Query OK, 1 row(s) in set (0.000980s)
-   ```
+  ```
 - **STDDEV**
@@ -896,7 +899,7 @@ TDengine supports aggregations over data, they are listed below:
   ======================================
               13.40000 |          223 |
   Query OK, 1 row(s) in set (0.001123s)
   taos> SELECT MAX(current), MAX(voltage) FROM d1001;
       max(current)     | max(voltage) |
   ======================================
@@ -937,8 +940,6 @@ TDengine supports aggregations over data, they are listed below:
   Query OK, 1 row(s) in set (0.001023s)
   ```
- 
 - **LAST**
   ```mysql
@@ -972,7 +973,7 @@ TDengine supports aggregations over data, they are listed below:
   ```
 - **TOP**
    ```mysql
    SELECT TOP(field_name, K) FROM { tb_name | stb_name } [WHERE clause];
    ```
@@ -1029,7 +1030,7 @@ TDengine supports aggregations over data, they are listed below:
    2018-10-03 14:38:15.000 |                218 |
    2018-10-03 14:38:16.650 |                218 |
    Query OK, 2 row(s) in set (0.001332s)
    taos> SELECT BOTTOM(current, 2) FROM d1001;
            ts            |  bottom(current, 2)  |
    =================================================
@@ -1092,7 +1093,7 @@ TDengine supports aggregations over data, they are listed below:
    =======================
                12.30000 |
    Query OK, 1 row(s) in set (0.001238s)
    taos> SELECT LAST_ROW(current) FROM d1002;
    last_row(current)   |
    =======================
@@ -1146,7 +1147,7 @@ TDengine supports aggregations over data, they are listed below:
    ============================
                5.000000000 |
    Query OK, 1 row(s) in set (0.001792s)
    taos> SELECT SPREAD(voltage) FROM d1001;
        spread(voltage)      |
    ============================
@@ -1172,7 +1173,7 @@ TDengine supports aggregations over data, they are listed below:
 ## <a class="anchor" id="aggregation"></a> Time-dimension Aggregation
-TDengine supports aggregating by intervals. Data in a table can partitioned by intervals and aggregated to generate results. For example, a temperature sensor collects data once per second, but the average temperature needs to be queried every 10 minutes. This aggregation is suitable for down sample operation, and the syntax is as follows:
+TDengine supports aggregating by intervals (time range). Data in a table can partitioned by intervals and aggregated to generate results. For example, a temperature sensor collects data once per second, but the average temperature needs to be queried every 10 minutes. This aggregation is suitable for down sample operation, and the syntax is as follows:
 ```mysql
 SELECT function_list FROM tb_name
@@ -1235,12 +1236,12 @@ SELECT AVG(current), MAX(current), LEASTSQUARES(current, start_val, step_val), P
 **Restrictions on group by**
-TAOS SQL supports group by operation on tags, tbnames and ordinary columns, required that only one column and whichhas less than 100,000 unique values.
+TAOS SQL supports group by operation on tags, tbnames and ordinary columns, required that only one column and which has less than 100,000 unique values.
 **Restrictions on join operation**
-TAOS SQL supports join columns of two tables by Primary Key timestamp between them, and does not support four operations after tables aggregated for the time being.
+TAOS SQL supports join columns of two tables by Primary Key timestamp between them, and does not support four arithmetic operations after tables aggregated for the time being.
 **Availability of is no null**
 Is not null supports all types of columns. Non-null expression is < > "" and only applies to columns of non-numeric types.
\ No newline at end of file
--- a/packaging/tools/make_install.sh
+++ b/packaging/tools/make_install.sh
@@ -20,41 +20,33 @@ fi
 # Dynamic directory
-data_dir="/var/lib/taos"
 if [ "$osType" != "Darwin" ]; then
+    data_dir="/var/lib/taos"
    log_dir="/var/log/taos"
-else
-    log_dir=~/TDengine/log
-fi
-data_link_dir="/usr/local/taos/data"
-log_link_dir="/usr/local/taos/log"
-if [ "$osType" != "Darwin" ]; then
    cfg_install_dir="/etc/taos"
-else
-    cfg_install_dir="/usr/local/Cellar/tdengine/${verNumber}/taos"
-fi
-if [ "$osType" != "Darwin" ]; then
    bin_link_dir="/usr/bin"
    lib_link_dir="/usr/lib"
    lib64_link_dir="/usr/lib64"
    inc_link_dir="/usr/include"
-fi
-#install main path
-if [ "$osType" != "Darwin" ]; then
    install_main_dir="/usr/local/taos"
+    bin_dir="/usr/local/taos/bin"
 else
+    data_dir="/usr/local/var/lib/taos"
+    log_dir="/usr/local/var/log/taos"
+    cfg_install_dir="/usr/local/etc/taos"
+    bin_link_dir="/usr/local/bin"
+    lib_link_dir="/usr/local/lib"
+    inc_link_dir="/usr/local/include"
    install_main_dir="/usr/local/Cellar/tdengine/${verNumber}"
-fi
-# old bin dir
+    bin_dir="/usr/local/Cellar/tdengine/${verNumber}/bin"
-if [ "$osType" != "Darwin" ]; then
-     bin_dir="/usr/local/taos/bin"
-else
-     bin_dir="/usr/local/Cellar/tdengine/${verNumber}/bin"
 fi
 service_config_dir="/etc/systemd/system"
@@ -144,12 +136,13 @@ function install_main_path() {
 function install_bin() {
    # Remove links
+    ${csudo} rm -f ${bin_link_dir}/taos     || :
+    ${csudo} rm -f ${bin_link_dir}/taosd    || :
+    ${csudo} rm -f ${bin_link_dir}/taosdemo || :
+    ${csudo} rm -f ${bin_link_dir}/taosdump || :
    if [ "$osType" != "Darwin" ]; then
-        ${csudo} rm -f ${bin_link_dir}/taos     || :
-        ${csudo} rm -f ${bin_link_dir}/taosd    || :
-        ${csudo} rm -f ${bin_link_dir}/taosdemo || :
        ${csudo} rm -f ${bin_link_dir}/perfMonitor || :
-        ${csudo} rm -f ${bin_link_dir}/taosdump || :
        ${csudo} rm -f ${bin_link_dir}/set_core || :
        ${csudo} rm -f ${bin_link_dir}/rmtaos   || :
    fi
@@ -167,11 +160,12 @@ function install_bin() {
    ${csudo} chmod 0555 ${install_main_dir}/bin/*
    #Make link
+    [ -x ${install_main_dir}/bin/taos ]      && ${csudo} ln -s ${install_main_dir}/bin/taos ${bin_link_dir}/taos    || :
+    [ -x ${install_main_dir}/bin/taosd ]     && ${csudo} ln -s ${install_main_dir}/bin/taosd ${bin_link_dir}/taosd   || :
+    [ -x ${install_main_dir}/bin/taosdump ]  && ${csudo} ln -s ${install_main_dir}/bin/taosdump ${bin_link_dir}/taosdump || :
+    [ -x ${install_main_dir}/bin/taosdemo ]  && ${csudo} ln -s ${install_main_dir}/bin/taosdemo ${bin_link_dir}/taosdemo || :
    if [ "$osType" != "Darwin" ]; then
-        [ -x ${install_main_dir}/bin/taos ]      && ${csudo} ln -s ${install_main_dir}/bin/taos ${bin_link_dir}/taos    || :
-        [ -x ${install_main_dir}/bin/taosd ]     && ${csudo} ln -s ${install_main_dir}/bin/taosd ${bin_link_dir}/taosd   || :
-        [ -x ${install_main_dir}/bin/taosdump ]  && ${csudo} ln -s ${install_main_dir}/bin/taosdump ${bin_link_dir}/taosdump || :
-        [ -x ${install_main_dir}/bin/taosdemo ]  && ${csudo} ln -s ${install_main_dir}/bin/taosdemo ${bin_link_dir}/taosdemo || :
        [ -x ${install_main_dir}/bin/perfMonitor ]  && ${csudo} ln -s ${install_main_dir}/bin/perfMonitor ${bin_link_dir}/perfMonitor || :
        [ -x ${install_main_dir}/set_core.sh ]  && ${csudo} ln -s ${install_main_dir}/bin/set_core.sh ${bin_link_dir}/set_core || :
    fi
@@ -249,7 +243,10 @@ function install_lib() {
          ${csudo} ln -sf ${lib64_link_dir}/libtaos.so.1 ${lib64_link_dir}/libtaos.so
        fi
    else
-        ${csudo} cp -Rf ${binary_dir}/build/lib/libtaos.* ${install_main_dir}/driver && ${csudo} chmod 777 ${install_main_dir}/driver/*
+        ${csudo} cp -Rf ${binary_dir}/build/lib/libtaos.${verNumber}.dylib ${install_main_dir}/driver && ${csudo} chmod 777 ${install_main_dir}/driver/*
+        ${csudo} ln -sf ${install_main_dir}/driver/libtaos.* ${lib_link_dir}/libtaos.1.dylib
+        ${csudo} ln -sf ${lib_link_dir}/libtaos.1.dylib ${lib_link_dir}/libtaos.dylib
    fi
    install_jemalloc
@@ -288,18 +285,14 @@ function install_config() {
 }
 function install_log() {
-    if [ "$osType" != "Darwin" ]; then
+    ${csudo} rm -rf ${log_dir}  || :
-            ${csudo} rm -rf ${log_dir}  || :
+    ${csudo} mkdir -p ${log_dir} && ${csudo} chmod 777 ${log_dir}
-            ${csudo} mkdir -p ${log_dir} && ${csudo} chmod 777 ${log_dir}
+    ${csudo} ln -s ${log_dir} ${install_main_dir}/log
-            ${csudo} ln -s ${log_dir} ${install_main_dir}/log
-    fi
 }
 function install_data() {
-    if [ "$osType" != "Darwin" ]; then
+    ${csudo} mkdir -p ${data_dir}
-        ${csudo} mkdir -p ${data_dir}
+    ${csudo} ln -s ${data_dir} ${install_main_dir}/data
-        ${csudo} ln -s ${data_dir} ${install_main_dir}/data
-    fi
 }
 function install_connector() {
@@ -496,10 +489,7 @@ function install_TDengine() {
    install_main_path
-    if [ "$osType" != "Darwin" ]; then
+    install_data
-        install_data
-    fi
    install_log
    install_header
    install_lib

--- a/src/client/inc/tscUtil.h
+++ b/src/client/inc/tscUtil.h
@@ -318,6 +318,7 @@ void doAddGroupColumnForSubquery(SQueryInfo* pQueryInfo, int32_t tagIndex, SSqlC
 int16_t tscGetJoinTagColIdByUid(STagCond* pTagCond, uint64_t uid);
 int16_t tscGetTagColIndexById(STableMeta* pTableMeta, int16_t colId);
+int32_t doInitSubState(SSqlObj* pSql, int32_t numOfSubqueries);
 void tscPrintSelNodeList(SSqlObj* pSql, int32_t subClauseIndex);

--- a/src/client/src/TSDBJNIConnector.c
+++ b/src/client/src/TSDBJNIConnector.c
--- a/src/client/src/tscSQLParser.c
+++ b/src/client/src/tscSQLParser.c
@@ -22,6 +22,7 @@
 #include <qSqlparser.h>
 #include "os.h"
+#include "regex.h"
 #include "qPlan.h"
 #include "qSqlparser.h"
 #include "qTableMeta.h"
@@ -278,6 +279,8 @@ static uint8_t convertRelationalOperator(SStrToken *pToken) {
      return TSDB_BINARY_OP_REMAINDER;
    case TK_LIKE:
      return TSDB_RELATION_LIKE;
+    case TK_MATCH:
+      return TSDB_RELATION_MATCH;
    case TK_ISNULL:
      return TSDB_RELATION_ISNULL;
    case TK_NOTNULL:
@@ -430,7 +433,7 @@ int32_t readFromFile(char *name, uint32_t *len, void **buf) {
 int32_t handleUserDefinedFunc(SSqlObj* pSql, struct SSqlInfo* pInfo) {
-  const char *msg1 = "function name is too long";
+  const char *msg1 = "invalidate function name";
  const char *msg2 = "path is too long";
  const char *msg3 = "invalid outputtype";
  const char *msg4 = "invalid script";
@@ -447,7 +450,10 @@ int32_t handleUserDefinedFunc(SSqlObj* pSql, struct SSqlInfo* pInfo) {
      }
      createInfo->name.z[createInfo->name.n] = 0;
+      // funcname's naming rule is same to column 
+      if (validateColumnName(createInfo->name.z) != TSDB_CODE_SUCCESS) {
+        return  invalidOperationMsg(tscGetErrorMsgPayload(pCmd), msg1);
+      }
      strdequote(createInfo->name.z);
      if (strlen(createInfo->name.z) >= TSDB_FUNC_NAME_LEN) {
@@ -3773,6 +3779,9 @@ static int32_t doExtractColumnFilterInfo(SSqlCmd* pCmd, SQueryInfo* pQueryInfo,
    case TK_LIKE:
      pColumnFilter->lowerRelOptr = TSDB_RELATION_LIKE;
      break;
+    case TK_MATCH:
+      pColumnFilter->lowerRelOptr = TSDB_RELATION_MATCH;
+      break;
    case TK_ISNULL:
      pColumnFilter->lowerRelOptr = TSDB_RELATION_ISNULL;
      break;
@@ -3836,9 +3845,15 @@ static int32_t tablenameListToString(tSqlExpr* pExpr, SStringBuilder* sb) {
  return TSDB_CODE_SUCCESS;
 }
-static int32_t tablenameCondToString(tSqlExpr* pExpr, SStringBuilder* sb) {
+static int32_t tablenameCondToString(tSqlExpr* pExpr, uint32_t opToken, SStringBuilder* sb) {
-  taosStringBuilderAppendStringLen(sb, QUERY_COND_REL_PREFIX_LIKE, QUERY_COND_REL_PREFIX_LIKE_LEN);
+  assert(opToken == TK_LIKE || opToken == TK_MATCH);
-  taosStringBuilderAppendString(sb, pExpr->value.pz);
+  if (opToken == TK_LIKE) {
+    taosStringBuilderAppendStringLen(sb, QUERY_COND_REL_PREFIX_LIKE, QUERY_COND_REL_PREFIX_LIKE_LEN);
+    taosStringBuilderAppendString(sb, pExpr->value.pz);
+  } else if (opToken == TK_MATCH) {
+    taosStringBuilderAppendStringLen(sb, QUERY_COND_REL_PREFIX_MATCH, QUERY_COND_REL_PREFIX_MATCH_LEN);
+    taosStringBuilderAppendString(sb, pExpr->value.pz);
+  }
  return TSDB_CODE_SUCCESS;
 }
@@ -3859,7 +3874,7 @@ static int32_t checkColumnFilterInfo(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, SCol
  STableMeta* pTableMeta = pTableMetaInfo->pTableMeta;
  SSchema*    pSchema = tscGetTableColumnSchema(pTableMeta, pIndex->columnIndex);
  int32_t     ret = 0;
-  const char* msg1 = "non binary column not support like operator";
+  const char* msg1 = "non binary column not support like/match operator";
  const char* msg2 = "binary column not support this operator";  
  const char* msg3 = "bool column not support this operator";
  const char* msg4 = "primary key not support this operator";
@@ -3887,12 +3902,13 @@ static int32_t checkColumnFilterInfo(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, SCol
      && pExpr->tokenId != TK_ISNULL
      && pExpr->tokenId != TK_NOTNULL
      && pExpr->tokenId != TK_LIKE
+      && pExpr->tokenId != TK_MATCH
      && pExpr->tokenId != TK_IN) {
      ret = invalidOperationMsg(tscGetErrorMsgPayload(pCmd), msg2);
      goto _err_ret;
    }
  } else {
-    if (pExpr->tokenId == TK_LIKE) {
+    if (pExpr->tokenId == TK_LIKE || pExpr->tokenId == TK_MATCH) {
      ret = invalidOperationMsg(tscGetErrorMsgPayload(pCmd), msg1);
      goto _err_ret;
    }
@@ -3940,12 +3956,12 @@ static int32_t getTablenameCond(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, tSqlExpr*
  if (pTableCond->tokenId == TK_IN) {
    ret = tablenameListToString(pRight, sb);
-  } else if (pTableCond->tokenId == TK_LIKE) {
+  } else if (pTableCond->tokenId == TK_LIKE || pTableCond->tokenId == TK_MATCH) {
    if (pRight->tokenId != TK_STRING) {
      return invalidOperationMsg(tscGetErrorMsgPayload(pCmd), msg1);
    }
-    ret = tablenameCondToString(pRight, sb);
+    ret = tablenameCondToString(pRight, pTableCond->tokenId, sb);
  }
  if (ret != TSDB_CODE_SUCCESS) {
@@ -4394,7 +4410,7 @@ static bool validateJoinExprNode(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, tSqlExpr
 }
 static bool validTableNameOptr(tSqlExpr* pExpr) {
-  const char nameFilterOptr[] = {TK_IN, TK_LIKE};
+  const char nameFilterOptr[] = {TK_IN, TK_LIKE, TK_MATCH};
  for (int32_t i = 0; i < tListLen(nameFilterOptr); ++i) {
    if (pExpr->tokenId == nameFilterOptr[i]) {
@@ -4486,6 +4502,45 @@ static int32_t validateLikeExpr(tSqlExpr* pExpr, STableMeta* pTableMeta, int32_t
  return TSDB_CODE_SUCCESS;
 }
+// check for match expression
+static int32_t validateMatchExpr(tSqlExpr* pExpr, STableMeta* pTableMeta, int32_t index, char* msgBuf) {
+  const char* msg1 = "regular expression string should be less than %d characters";
+  const char* msg2 = "illegal column type for match";
+  const char* msg3 = "invalid regular expression";
+  tSqlExpr* pLeft  = pExpr->pLeft;
+  tSqlExpr* pRight = pExpr->pRight;
+  if (pExpr->tokenId == TK_MATCH) {
+    if (pRight->value.nLen > tsMaxRegexStringLen) {
+      char tmp[64] = {0};
+      sprintf(tmp, msg1, tsMaxRegexStringLen);
+      return invalidOperationMsg(msgBuf, tmp);
+    }
+    SSchema* pSchema = tscGetTableSchema(pTableMeta);
+    if ((!isTablenameToken(&pLeft->columnName)) && !IS_VAR_DATA_TYPE(pSchema[index].type)) {
+      return invalidOperationMsg(msgBuf, msg2);
+    }
+    int errCode = 0;
+    regex_t regex;
+    char    regErrBuf[256] = {0};
+    const char* pattern = pRight->value.pz;
+    int cflags = REG_EXTENDED;
+    if ((errCode = regcomp(&regex, pattern, cflags)) != 0) {
+      regerror(errCode, &regex, regErrBuf, sizeof(regErrBuf));
+      tscError("Failed to compile regex pattern %s. reason %s", pattern, regErrBuf);
+      return invalidOperationMsg(msgBuf, msg3);
+    }
+    regfree(&regex);
+  }
+  return TSDB_CODE_SUCCESS;
+}
 int32_t handleNeOptr(tSqlExpr** rexpr, tSqlExpr* expr) {
  tSqlExpr* left = tSqlExprClone(expr);
  tSqlExpr* right = expr;
@@ -4537,6 +4592,12 @@ static int32_t handleExprInQueryCond(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, tSql
    return code;
  }
+  // validate the match expression
+  code = validateMatchExpr(*pExpr, pTableMeta, index.columnIndex, tscGetErrorMsgPayload(pCmd));
+  if (code != TSDB_CODE_SUCCESS) {
+    return code;
+  }
  SSchema* pSchema = tscGetTableColumnSchema(pTableMeta, index.columnIndex);
  if (pSchema->type == TSDB_DATA_TYPE_TIMESTAMP && index.columnIndex == PRIMARYKEY_TIMESTAMP_COL_INDEX) {  // query on time range
    if (!validateJoinExprNode(pCmd, pQueryInfo, *pExpr, &index)) {
@@ -4864,65 +4925,66 @@ static int32_t setTableCondForSTableQuery(SSqlCmd* pCmd, SQueryInfo* pQueryInfo,
  STagCond* pTagCond = &pQueryInfo->tagCond;
  pTagCond->tbnameCond.uid = pTableMetaInfo->pTableMeta->id.uid;
-  assert(pExpr->tokenId == TK_LIKE || pExpr->tokenId == TK_IN);
+  assert(pExpr->tokenId == TK_LIKE || pExpr->tokenId == TK_MATCH || pExpr->tokenId == TK_IN);
-  if (pExpr->tokenId == TK_LIKE) {
+  if (pExpr->tokenId == TK_LIKE || pExpr->tokenId == TK_MATCH) {
    char* str = taosStringBuilderGetResult(sb, NULL);
    pQueryInfo->tagCond.tbnameCond.cond = strdup(str);
    pQueryInfo->tagCond.tbnameCond.len = (int32_t) strlen(str);
    return TSDB_CODE_SUCCESS;
-  }
+  } else {
+    SStringBuilder sb1;
-  SStringBuilder sb1; memset(&sb1, 0, sizeof(sb1));
+    memset(&sb1, 0, sizeof(sb1));
-  taosStringBuilderAppendStringLen(&sb1, QUERY_COND_REL_PREFIX_IN, QUERY_COND_REL_PREFIX_IN_LEN);
+    taosStringBuilderAppendStringLen(&sb1, QUERY_COND_REL_PREFIX_IN, QUERY_COND_REL_PREFIX_IN_LEN);
-  // remove the duplicated input table names
+    // remove the duplicated input table names
-  int32_t num = 0;
+    int32_t num = 0;
-  char*   tableNameString = taosStringBuilderGetResult(sb, NULL);
+    char*   tableNameString = taosStringBuilderGetResult(sb, NULL);
-  char** segments = strsplit(tableNameString + QUERY_COND_REL_PREFIX_IN_LEN, TBNAME_LIST_SEP, &num);
+    char** segments = strsplit(tableNameString + QUERY_COND_REL_PREFIX_IN_LEN, TBNAME_LIST_SEP, &num);
-  qsort(segments, num, POINTER_BYTES, tableNameCompar);
+    qsort(segments, num, POINTER_BYTES, tableNameCompar);
-  int32_t j = 1;
+    int32_t j = 1;
-  for (int32_t i = 1; i < num; ++i) {
+    for (int32_t i = 1; i < num; ++i) {
-    if (strcmp(segments[i], segments[i - 1]) != 0) {
+      if (strcmp(segments[i], segments[i - 1]) != 0) {
-      segments[j++] = segments[i];
+        segments[j++] = segments[i];
+      }
    }
-  }
+    num = j;
-  num = j;
-  char name[TSDB_DB_NAME_LEN] = {0};
+    char name[TSDB_DB_NAME_LEN] = {0};
-  tNameGetDbName(&pTableMetaInfo->name, name);
+    tNameGetDbName(&pTableMetaInfo->name, name);
-  SStrToken dbToken = { .type = TK_STRING, .z = name, .n = (uint32_t)strlen(name) };
+    SStrToken dbToken = {.type = TK_STRING, .z = name, .n = (uint32_t)strlen(name)};
-  for (int32_t i = 0; i < num; ++i) {
-    if (i >= 1) {
-      taosStringBuilderAppendStringLen(&sb1, TBNAME_LIST_SEP, 1);
-    }
-    char      idBuf[TSDB_TABLE_FNAME_LEN] = {0};
+    for (int32_t i = 0; i < num; ++i) {
-    int32_t   xlen = (int32_t)strlen(segments[i]);
+      if (i >= 1) {
-    SStrToken t = {.z = segments[i], .n = xlen, .type = TK_STRING};
+        taosStringBuilderAppendStringLen(&sb1, TBNAME_LIST_SEP, 1);
+      }
-    int32_t ret = setObjFullName(idBuf, account, &dbToken, &t, &xlen);
+      char      idBuf[TSDB_TABLE_FNAME_LEN] = {0};
-    if (ret != TSDB_CODE_SUCCESS) {
+      int32_t   xlen = (int32_t)strlen(segments[i]);
-      taosStringBuilderDestroy(&sb1);
+      SStrToken t = {.z = segments[i], .n = xlen, .type = TK_STRING};
-      tfree(segments);
-      invalidOperationMsg(tscGetErrorMsgPayload(pCmd), msg);
+      int32_t ret = setObjFullName(idBuf, account, &dbToken, &t, &xlen);
-      return ret;
+      if (ret != TSDB_CODE_SUCCESS) {
-    }
+        taosStringBuilderDestroy(&sb1);
+        tfree(segments);
-    taosStringBuilderAppendString(&sb1, idBuf);
+        invalidOperationMsg(tscGetErrorMsgPayload(pCmd), msg);
-  }
+        return ret;
+      }
-  char* str = taosStringBuilderGetResult(&sb1, NULL);
+      taosStringBuilderAppendString(&sb1, idBuf);
-  pQueryInfo->tagCond.tbnameCond.cond = strdup(str);
+    }
-  pQueryInfo->tagCond.tbnameCond.len = (int32_t) strlen(str);
-  taosStringBuilderDestroy(&sb1);
+    char* str = taosStringBuilderGetResult(&sb1, NULL);
-  tfree(segments);
+    pQueryInfo->tagCond.tbnameCond.cond = strdup(str);
-  return TSDB_CODE_SUCCESS;
+    pQueryInfo->tagCond.tbnameCond.len = (int32_t)strlen(str);
+    taosStringBuilderDestroy(&sb1);
+    tfree(segments);
+    return TSDB_CODE_SUCCESS;
+  }
 }
 int32_t mergeTimeRange(SSqlCmd* pCmd, STimeWindow* res, STimeWindow* win, int32_t optr) {
@@ -8109,7 +8171,7 @@ int32_t tscGetExprFilters(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, SArray* pSelect
 }
 static int32_t handleExprInHavingClause(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, SArray* pSelectNodeList, tSqlExpr* pExpr, int32_t sqlOptr) {
-  const char* msg1 = "non binary column not support like operator";
+  const char* msg1 = "non binary column not support like/match operator";
  const char* msg2 = "invalid operator for binary column in having clause";
  const char* msg3 = "invalid operator for bool column in having clause";
@@ -8161,11 +8223,12 @@ static int32_t handleExprInHavingClause(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, S
        && pExpr->tokenId != TK_ISNULL
        && pExpr->tokenId != TK_NOTNULL
        && pExpr->tokenId != TK_LIKE
+        && pExpr->tokenId != TK_MATCH
        ) {
      return invalidOperationMsg(tscGetErrorMsgPayload(pCmd), msg2);
    }
  } else {
-    if (pExpr->tokenId == TK_LIKE) {
+    if (pExpr->tokenId == TK_LIKE || pExpr->tokenId == TK_MATCH) {
      return invalidOperationMsg(tscGetErrorMsgPayload(pCmd), msg1);
    }

--- a/src/client/src/tscSubquery.c
+++ b/src/client/src/tscSubquery.c
@@ -2459,11 +2459,48 @@ static void doSendQueryReqs(SSchedMsg* pSchedMsg) {
  tfree(p);
 }
+static void doConcurrentlySendSubQueries(SSqlObj* pSql) {
+  SSubqueryState *pState = &pSql->subState;
+  // concurrently sent the query requests.
+  const int32_t MAX_REQUEST_PER_TASK = 8;
+  int32_t numOfTasks = (pState->numOfSub + MAX_REQUEST_PER_TASK - 1)/MAX_REQUEST_PER_TASK;
+  assert(numOfTasks >= 1);
+  int32_t num;
+  if (pState->numOfSub / numOfTasks == MAX_REQUEST_PER_TASK) {
+    num = MAX_REQUEST_PER_TASK;
+  } else {
+    num = pState->numOfSub / numOfTasks + 1;
+  }
+  tscDebug("0x%"PRIx64 " query will be sent by %d threads", pSql->self, numOfTasks);
+  for(int32_t j = 0; j < numOfTasks; ++j) {
+    SSchedMsg schedMsg = {0};
+    schedMsg.fp      = doSendQueryReqs;
+    schedMsg.ahandle = (void*)pSql;
+    schedMsg.thandle = NULL;
+    SPair* p = calloc(1, sizeof(SPair));
+    p->first  = j * num;
+    if (j == numOfTasks - 1) {
+      p->second = pState->numOfSub;
+    } else {
+      p->second = (j + 1) * num;
+    }
+    schedMsg.msg = p;
+    taosScheduleTask(tscQhandle, &schedMsg);
+  }
+}
 int32_t tscHandleMasterSTableQuery(SSqlObj *pSql) {
  SSqlRes *pRes = &pSql->res;
  SSqlCmd *pCmd = &pSql->cmd;
-  // pRes->code check only serves in launching metric sub-queries
+  // pRes->code check only serves in launching super table sub-queries
  if (pRes->code == TSDB_CODE_TSC_QUERY_CANCELLED) {
    pCmd->command = TSDB_SQL_RETRIEVE_GLOBALMERGE;  // enable the abort of kill super table function.
    return pRes->code;
@@ -2474,22 +2511,23 @@ int32_t tscHandleMasterSTableQuery(SSqlObj *pSql) {
  pRes->qId = 0x1;  // hack the qhandle check
-  const uint32_t nBufferSize = (1u << 18u);  // 256KB
+  const uint32_t nBufferSize = (1u << 18u);  // 256KB, default buffer size
  SQueryInfo     *pQueryInfo = tscGetQueryInfo(pCmd);
  STableMetaInfo *pTableMetaInfo = tscGetMetaInfo(pQueryInfo, 0);
  SSubqueryState *pState = &pSql->subState;
-  pState->numOfSub = 0;
+  int32_t numOfSub = (pTableMetaInfo->pVgroupTables == NULL) ? pTableMetaInfo->vgroupList->numOfVgroups
-  if (pTableMetaInfo->pVgroupTables == NULL) {
+                                                             : (int32_t)taosArrayGetSize(pTableMetaInfo->pVgroupTables);
-    pState->numOfSub = pTableMetaInfo->vgroupList->numOfVgroups;
-  } else {
+  int32_t ret = doInitSubState(pSql, numOfSub);
-    pState->numOfSub = (int32_t)taosArrayGetSize(pTableMetaInfo->pVgroupTables);
+  if (ret != 0) {
+    tscAsyncResultOnError(pSql);
+    return ret;
  }
-  assert(pState->numOfSub > 0);
+  ret = tscCreateGlobalMergerEnv(pQueryInfo, &pMemoryBuf, pSql->subState.numOfSub, &pDesc, nBufferSize, pSql->self);
-  int32_t ret = tscCreateGlobalMergerEnv(pQueryInfo, &pMemoryBuf, pSql->subState.numOfSub, &pDesc, nBufferSize, pSql->self);
  if (ret != 0) {
    pRes->code = ret;
    tscAsyncResultOnError(pSql);
@@ -2499,32 +2537,6 @@ int32_t tscHandleMasterSTableQuery(SSqlObj *pSql) {
  }
  tscDebug("0x%"PRIx64" retrieved query data from %d vnode(s)", pSql->self, pState->numOfSub);
-  pSql->pSubs = calloc(pState->numOfSub, POINTER_BYTES);
-  if (pSql->pSubs == NULL) {
-    tfree(pSql->pSubs);
-    pRes->code = TSDB_CODE_TSC_OUT_OF_MEMORY;
-    tscDestroyGlobalMergerEnv(pMemoryBuf, pDesc,pState->numOfSub);
-    tscAsyncResultOnError(pSql);
-    return ret;
-  }
-  if (pState->states == NULL) {
-    pState->states = calloc(pState->numOfSub, sizeof(*pState->states));
-    if (pState->states == NULL) {
-      pRes->code = TSDB_CODE_TSC_OUT_OF_MEMORY;
-      tscDestroyGlobalMergerEnv(pMemoryBuf, pDesc,pState->numOfSub);
-      tscAsyncResultOnError(pSql);
-      return ret;
-    }
-    pthread_mutex_init(&pState->mutex, NULL);
-  }
-  memset(pState->states, 0, sizeof(*pState->states) * pState->numOfSub);
-  tscDebug("0x%"PRIx64" reset all sub states to 0", pSql->self);
  pRes->code = TSDB_CODE_SUCCESS;
  int32_t i = 0;
@@ -2545,8 +2557,8 @@ int32_t tscHandleMasterSTableQuery(SSqlObj *pSql) {
      break;
    }
-    trs->subqueryIndex  = i;
+    trs->subqueryIndex = i;
-    trs->pParentSql     = pSql;
+    trs->pParentSql    = pSql;
    SSqlObj *pNew = tscCreateSTableSubquery(pSql, trs, NULL);
    if (pNew == NULL) {
@@ -2582,39 +2594,7 @@ int32_t tscHandleMasterSTableQuery(SSqlObj *pSql) {
    return pRes->code;
  }
-  // concurrently sent the query requests.
+  doConcurrentlySendSubQueries(pSql);
-  const int32_t MAX_REQUEST_PER_TASK = 8;
-  int32_t numOfTasks = (pState->numOfSub + MAX_REQUEST_PER_TASK - 1)/MAX_REQUEST_PER_TASK;
-  assert(numOfTasks >= 1);
-  int32_t num;
-  if (pState->numOfSub / numOfTasks == MAX_REQUEST_PER_TASK) {
-    num = MAX_REQUEST_PER_TASK;
-  } else {
-    num = pState->numOfSub / numOfTasks + 1;
-  }
-  tscDebug("0x%"PRIx64 " query will be sent by %d threads", pSql->self, numOfTasks);
-  for(int32_t j = 0; j < numOfTasks; ++j) {
-    SSchedMsg schedMsg = {0};
-    schedMsg.fp      = doSendQueryReqs;
-    schedMsg.ahandle = (void*)pSql;
-    schedMsg.thandle = NULL;
-    SPair* p = calloc(1, sizeof(SPair));
-    p->first  = j * num;
-    if (j == numOfTasks - 1) {
-      p->second = pState->numOfSub;
-    } else {
-      p->second = (j + 1) * num;
-    }
-    schedMsg.msg = p;
-    taosScheduleTask(tscQhandle, &schedMsg);
-  }
  return TSDB_CODE_SUCCESS;
 }

--- a/src/client/src/tscSystem.c
+++ b/src/client/src/tscSystem.c
@@ -122,6 +122,10 @@ int32_t tscAcquireRpc(const char *key, const char *user, const char *secretEncry
 void taos_init_imp(void) {
  char temp[128] = {0};
+  // In the APIs of other program language, taos_cleanup is not available yet.
+  // So, to make sure taos_cleanup will be invoked to clean up the allocated resource to suppress the valgrind warning.
+  atexit(taos_cleanup);
  errno = TSDB_CODE_SUCCESS;
  srand(taosGetTimestampSec());
@@ -197,10 +201,6 @@ void taos_init_imp(void) {
  tscRefId = taosOpenRef(200, tscCloseTscObj);
-  // In the APIs of other program language, taos_cleanup is not available yet.
-  // So, to make sure taos_cleanup will be invoked to clean up the allocated resource to suppress the valgrind warning.
-  atexit(taos_cleanup);
  tscDebug("client is initialized successfully");
 }

--- a/src/client/src/tscUtil.c
+++ b/src/client/src/tscUtil.c
@@ -3944,6 +3944,21 @@ static void tscSubqueryCompleteCallback(void* param, TAOS_RES* tres, int code) {
  taos_fetch_rows_a(tres, tscSubqueryRetrieveCallback, param);
 }
+int32_t doInitSubState(SSqlObj* pSql, int32_t numOfSubqueries) {
+  assert(pSql->subState.numOfSub == 0 && pSql->pSubs == NULL && pSql->subState.states == NULL);
+  pSql->subState.numOfSub = numOfSubqueries;
+  pSql->pSubs = calloc(pSql->subState.numOfSub, POINTER_BYTES);
+  pSql->subState.states = calloc(pSql->subState.numOfSub, sizeof(int8_t));
+  int32_t code = pthread_mutex_init(&pSql->subState.mutex, NULL);
+  if (pSql->pSubs == NULL || pSql->subState.states == NULL || code != 0) {
+    return TSDB_CODE_TSC_OUT_OF_MEMORY;
+  }
+  return TSDB_CODE_SUCCESS;
+}
 // do execute the query according to the query execution plan
 void executeQuery(SSqlObj* pSql, SQueryInfo* pQueryInfo) {
  int32_t code = TSDB_CODE_SUCCESS;
@@ -3959,16 +3974,8 @@ void executeQuery(SSqlObj* pSql, SQueryInfo* pQueryInfo) {
  }
  if (taosArrayGetSize(pQueryInfo->pUpstream) > 0) {  // nest query. do execute it firstly
-    assert(pSql->subState.numOfSub == 0);
+    code = doInitSubState(pSql, (int32_t) taosArrayGetSize(pQueryInfo->pUpstream));
-    pSql->subState.numOfSub = (int32_t) taosArrayGetSize(pQueryInfo->pUpstream);
+    if (code != TSDB_CODE_SUCCESS) {
-    assert(pSql->pSubs == NULL);
-    pSql->pSubs = calloc(pSql->subState.numOfSub, POINTER_BYTES);
-    assert(pSql->subState.states == NULL);
-    pSql->subState.states = calloc(pSql->subState.numOfSub, sizeof(int8_t));
-    code = pthread_mutex_init(&pSql->subState.mutex, NULL);
-    if (pSql->pSubs == NULL || pSql->subState.states == NULL || code != TSDB_CODE_SUCCESS) {
-      code = TSDB_CODE_TSC_OUT_OF_MEMORY;
      goto _error;
    }
@@ -4315,7 +4322,9 @@ void tscTryQueryNextClause(SSqlObj* pSql, __async_cb_func_t fp) {
  }
  tfree(pSql->pSubs);
+  tfree(pSql->subState.states);
  pSql->subState.numOfSub = 0;
+  pthread_mutex_destroy(&pSql->subState.mutex);
  pSql->fp = fp;

--- a/src/common/inc/texpr.h
+++ b/src/common/inc/texpr.h
@@ -33,9 +33,11 @@ struct SSchema;
 #define QUERY_COND_REL_PREFIX_IN "IN|"
 #define QUERY_COND_REL_PREFIX_LIKE "LIKE|"
+#define QUERY_COND_REL_PREFIX_MATCH "MATCH|"
 #define QUERY_COND_REL_PREFIX_IN_LEN   3
 #define QUERY_COND_REL_PREFIX_LIKE_LEN 5
+#define QUERY_COND_REL_PREFIX_MATCH_LEN 6
 typedef bool (*__result_filter_fn_t)(const void *, void *);
 typedef void (*__do_filter_suppl_fn_t)(void *, void *);

--- a/src/common/inc/tglobal.h
+++ b/src/common/inc/tglobal.h
@@ -74,6 +74,7 @@ extern int8_t   tsKeepOriginalColumnName;
 // client
 extern int32_t tsMaxSQLStringLen;
 extern int32_t tsMaxWildCardsLen;
+extern int32_t tsMaxRegexStringLen;
 extern int8_t  tsTscEnableRecordSql;
 extern int32_t tsMaxNumOfOrderedResults;
 extern int32_t tsMinSlidingTime;

--- a/src/common/src/tdataformat.c
+++ b/src/common/src/tdataformat.c
@@ -448,6 +448,7 @@ static void tdAppendDataRowToDataCol(SDataRow row, STSchema *pSchema, SDataCols
  int dcol = 0;
  while (dcol < pCols->numOfCols) {
+    bool setCol = 0;
    SDataCol *pDataCol = &(pCols->cols[dcol]);
    if (rcol >= schemaNCols(pSchema)) {
      dataColAppendVal(pDataCol, getNullValue(pDataCol->type), pCols->numOfRows, pCols->maxPoints);
@@ -458,13 +459,14 @@ static void tdAppendDataRowToDataCol(SDataRow row, STSchema *pSchema, SDataCols
    STColumn *pRowCol = schemaColAt(pSchema, rcol);
    if (pRowCol->colId == pDataCol->colId) {
      void *value = tdGetRowDataOfCol(row, pRowCol->type, pRowCol->offset + TD_DATA_ROW_HEAD_SIZE);
+      if(!isNull(value, pDataCol->type)) setCol = 1;
      dataColAppendVal(pDataCol, value, pCols->numOfRows, pCols->maxPoints);
      dcol++;
      rcol++;
    } else if (pRowCol->colId < pDataCol->colId) {
      rcol++;
    } else {
-      if(forceSetNull) {
+      if(forceSetNull || setCol) {
        dataColAppendVal(pDataCol, getNullValue(pDataCol->type), pCols->numOfRows, pCols->maxPoints);
      }
      dcol++;
@@ -482,6 +484,7 @@ static void tdAppendKvRowToDataCol(SKVRow row, STSchema *pSchema, SDataCols *pCo
  int nRowCols = kvRowNCols(row);
  while (dcol < pCols->numOfCols) {
+    bool setCol = 0;
    SDataCol *pDataCol = &(pCols->cols[dcol]);
    if (rcol >= nRowCols || rcol >= schemaNCols(pSchema)) {
      dataColAppendVal(pDataCol, getNullValue(pDataCol->type), pCols->numOfRows, pCols->maxPoints);
@@ -493,13 +496,14 @@ static void tdAppendKvRowToDataCol(SKVRow row, STSchema *pSchema, SDataCols *pCo
    if (colIdx->colId == pDataCol->colId) {
      void *value = tdGetKvRowDataOfCol(row, colIdx->offset);
+      if(!isNull(value, pDataCol->type)) setCol = 1;
      dataColAppendVal(pDataCol, value, pCols->numOfRows, pCols->maxPoints);
      ++dcol;
      ++rcol;
    } else if (colIdx->colId < pDataCol->colId) {
      ++rcol;
    } else {
-      if (forceSetNull) {
+      if(forceSetNull || setCol) {
        dataColAppendVal(pDataCol, getNullValue(pDataCol->type), pCols->numOfRows, pCols->maxPoints);
      }
      ++dcol;
@@ -518,7 +522,6 @@ void tdAppendMemRowToDataCol(SMemRow row, STSchema *pSchema, SDataCols *pCols, b
  }
 }
-//TODO: refactor this function to eliminate additional memory copy
 int tdMergeDataCols(SDataCols *target, SDataCols *source, int rowsToMerge, int *pOffset, bool forceSetNull) {
  ASSERT(rowsToMerge > 0 && rowsToMerge <= source->numOfRows);
  ASSERT(target->numOfCols == source->numOfCols);
@@ -534,7 +537,7 @@ int tdMergeDataCols(SDataCols *target, SDataCols *source, int rowsToMerge, int *
    ASSERT(target->numOfRows + rowsToMerge <= target->maxPoints);
    for (int i = 0; i < rowsToMerge; i++) {
      for (int j = 0; j < source->numOfCols; j++) {
-        if (source->cols[j].len > 0) {
+        if (source->cols[j].len > 0 || target->cols[j].len > 0) {
          dataColAppendVal(target->cols + j, tdGetColDataOfRow(source->cols + j, i + (*pOffset)), target->numOfRows,
                           target->maxPoints);
        }
@@ -578,7 +581,7 @@ static void tdMergeTwoDataCols(SDataCols *target, SDataCols *src1, int *iter1, i
    if (key1 < key2) {
      for (int i = 0; i < src1->numOfCols; i++) {
        ASSERT(target->cols[i].type == src1->cols[i].type);
-        if (src1->cols[i].len > 0) {
+        if (src1->cols[i].len > 0 || target->cols[i].len > 0) {
          dataColAppendVal(&(target->cols[i]), tdGetColDataOfRow(src1->cols + i, *iter1), target->numOfRows,
                           target->maxPoints);
        }
@@ -596,6 +599,8 @@ static void tdMergeTwoDataCols(SDataCols *target, SDataCols *src1, int *iter1, i
          } else if(!forceSetNull && key1 == key2 && src1->cols[i].len > 0) {
            dataColAppendVal(&(target->cols[i]), tdGetColDataOfRow(src1->cols + i, *iter1), target->numOfRows,
                             target->maxPoints);
+          } else if(target->cols[i].len > 0) {
+            dataColSetNullAt(&target->cols[i], target->numOfRows);
          }
        }
        target->numOfRows++;

--- a/src/common/src/texpr.c
+++ b/src/common/src/texpr.c
@@ -430,6 +430,17 @@ tExprNode* exprTreeFromTableName(const char* tbnameCond) {
    pVal->nType = TSDB_DATA_TYPE_BINARY;
    pVal->nLen = (int32_t)len;
+  } else if (strncmp(tbnameCond, QUERY_COND_REL_PREFIX_MATCH, QUERY_COND_REL_PREFIX_MATCH_LEN) == 0) {
+    right->nodeType = TSQL_NODE_VALUE;
+    expr->_node.optr = TSDB_RELATION_MATCH;
+    tVariant* pVal = exception_calloc(1, sizeof(tVariant));
+    right->pVal = pVal;
+    size_t len = strlen(tbnameCond + QUERY_COND_REL_PREFIX_MATCH_LEN) + 1;
+    pVal->pz = exception_malloc(len);
+    memcpy(pVal->pz, tbnameCond + QUERY_COND_REL_PREFIX_MATCH_LEN, len);
+    pVal->nType = TSDB_DATA_TYPE_BINARY;
+    pVal->nLen = (int32_t)len;
  } else if (strncmp(tbnameCond, QUERY_COND_REL_PREFIX_IN, QUERY_COND_REL_PREFIX_IN_LEN) == 0) {
    right->nodeType = TSQL_NODE_VALUE;
    expr->_node.optr = TSDB_RELATION_IN;

--- a/src/common/src/tglobal.c
+++ b/src/common/src/tglobal.c
@@ -85,6 +85,8 @@ int32_t tsCompressColData = -1;
 // client
 int32_t tsMaxSQLStringLen = TSDB_MAX_ALLOWED_SQL_LEN;
 int32_t tsMaxWildCardsLen = TSDB_PATTERN_STRING_DEFAULT_LEN;
+int32_t tsMaxRegexStringLen = TSDB_REGEX_STRING_DEFAULT_LEN;
 int8_t  tsTscEnableRecordSql = 0;
 // the maximum number of results for projection query on super table that are returned from

--- a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/TSDBResultSetBlockData.java
+++ b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/TSDBResultSetBlockData.java
@@ -32,6 +32,7 @@ import java.util.List;
 import com.taosdata.jdbc.utils.NullType;
 public class TSDBResultSetBlockData {
+    private static final int BINARY_LENGTH_OFFSET = 2;
    private int numOfRows = 0;
    private int rowIndex = 0;
@@ -404,10 +405,8 @@ public class TSDBResultSetBlockData {
            case TSDBConstants.TSDB_DATA_TYPE_BINARY: {
                ByteBuffer bb = (ByteBuffer) this.colData.get(col);
-                bb.position(fieldSize * this.rowIndex);
+                bb.position((fieldSize + BINARY_LENGTH_OFFSET) * this.rowIndex);
                int length = bb.getShort();
                byte[] dest = new byte[length];
                bb.get(dest, 0, length);
                if (NullType.isBinaryNull(dest, length)) {
@@ -419,16 +418,13 @@ public class TSDBResultSetBlockData {
            case TSDBConstants.TSDB_DATA_TYPE_NCHAR: {
                ByteBuffer bb = (ByteBuffer) this.colData.get(col);
-                bb.position(fieldSize * this.rowIndex);
+                bb.position((fieldSize + BINARY_LENGTH_OFFSET) * this.rowIndex);
                int length = bb.getShort();
                byte[] dest = new byte[length];
                bb.get(dest, 0, length);
                if (NullType.isNcharNull(dest, length)) {
                    return null;
                }
                try {
                    String charset = TaosGlobalConfig.getCharset();
                    return new String(dest, charset);

--- a/src/connector/jdbc/src/test/java/com/taosdata/jdbc/TSDBPreparedStatementTest.java
+++ b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/TSDBPreparedStatementTest.java
@@ -586,6 +586,130 @@ public class TSDBPreparedStatementTest {
        Assert.assertEquals(numOfRows, rows);
    }
+    @Test
+    public void bindDataQueryTest() throws SQLException {
+        Statement stmt = conn.createStatement();
+        stmt.execute("drop table if exists weather_test");
+        stmt.execute("create table weather_test(ts timestamp, f1 nchar(10), f2 binary(10)) tags (t1 int, t2 binary(10))");
+        int numOfRows = 1;
+        TSDBPreparedStatement s = (TSDBPreparedStatement) conn.prepareStatement("insert into ? using weather_test tags(?,?) (ts, f2) values(?, ?)");
+        s.setTableName("w2");
+        s.setTagInt(0, 1);
+        s.setTagString(1, "test");
+        ArrayList<Long> ts = new ArrayList<>();
+        for (int i = 0; i < numOfRows; i++) {
+            ts.add(System.currentTimeMillis() + i);
+        }
+        s.setTimestamp(0, ts);
+        ArrayList<String> s2 = new ArrayList<>();
+        for (int i = 0; i < numOfRows; i++) {
+            s2.add("test" + i % 4);
+        }
+        s.setString(1, s2, 10);
+        s.columnDataAddBatch();
+        s.columnDataExecuteBatch();
+        s.columnDataCloseBatch();
+        String sql = "select * from weather_test where t1 >= ? and t1 <= ?";
+        TSDBPreparedStatement s1 = (TSDBPreparedStatement) conn.prepareStatement(sql);
+        s1.setInt(1, 0);
+        s1.setInt(2, 10);
+        ResultSet rs = s1.executeQuery();
+        int rows = 0;
+        while (rs.next()) {
+            rows++;
+        }
+        Assert.assertEquals(numOfRows, rows);
+    }
+    @Test
+    public void setTagNullTest()throws SQLException {
+        Statement stmt = conn.createStatement();
+        stmt.execute("drop table if exists weather_test");
+        stmt.execute("create table weather_test(ts timestamp, c1 int) tags (t1 tinyint, t2 smallint, t3 int, t4 bigint, t5 float, t6 double, t7 bool, t8 binary(10), t9 nchar(10))");
+        int numOfRows = 1;
+        TSDBPreparedStatement s = (TSDBPreparedStatement) conn.prepareStatement("insert into ? using weather_test tags(?,?,?,?,?,?,?,?,?) values(?, ?)");
+        s.setTableName("w3");
+        s.setTagNull(0, TSDBConstants.TSDB_DATA_TYPE_TINYINT);
+        s.setTagNull(1, TSDBConstants.TSDB_DATA_TYPE_SMALLINT);
+        s.setTagNull(2, TSDBConstants.TSDB_DATA_TYPE_INT);
+        s.setTagNull(3, TSDBConstants.TSDB_DATA_TYPE_BIGINT);
+        s.setTagNull(4, TSDBConstants.TSDB_DATA_TYPE_FLOAT);
+        s.setTagNull(5, TSDBConstants.TSDB_DATA_TYPE_DOUBLE);
+        s.setTagNull(6, TSDBConstants.TSDB_DATA_TYPE_BOOL);
+        s.setTagNull(7, TSDBConstants.TSDB_DATA_TYPE_BINARY);
+        s.setTagNull(8, TSDBConstants.TSDB_DATA_TYPE_NCHAR);
+        ArrayList<Long> ts = new ArrayList<>();
+        for (int i = 0; i < numOfRows; i++) {
+            ts.add(System.currentTimeMillis() + i);
+        }
+        s.setTimestamp(0, ts);
+        ArrayList<Integer> s2 = new ArrayList<>();
+        for (int i = 0; i < numOfRows; i++) {
+            s2.add(i);
+        }
+        s.setInt(1, s2);
+        s.columnDataAddBatch();
+        s.columnDataExecuteBatch();
+        s.columnDataCloseBatch();
+    }
+    private String stringGenerator(int length) {
+        String source = "abcdefghijklmnopqrstuvwxyz";
+        StringBuilder sb = new StringBuilder();
+        Random rand = new Random();
+        for(int i = 0; i < length; i++) {
+            sb.append(source.charAt(rand.nextInt(26)));
+        }
+        return sb.toString();
+    }
+    @Test(expected = SQLException.class)
+    public void setMaxTableNameTest()throws SQLException {
+        Statement stmt = conn.createStatement();
+        stmt.execute("drop table if exists weather_test");
+        stmt.execute("create table weather_test(ts timestamp, c1 int) tags (t1 int)");
+        TSDBPreparedStatement s = (TSDBPreparedStatement) conn.prepareStatement("insert into ? using weather_test tags(?) values(?, ?)");
+        String tbname = stringGenerator(193);
+        s.setTableName(tbname);
+        s.setTagInt(0, 1);
+        int numOfRows = 1;
+        ArrayList<Long> ts = new ArrayList<>();
+        for (int i = 0; i < numOfRows; i++) {
+            ts.add(System.currentTimeMillis() + i);
+        }
+        s.setTimestamp(0, ts);
+        ArrayList<Integer> s2 = new ArrayList<>();
+        for (int i = 0; i < numOfRows; i++) {
+            s2.add(i);
+        }
+        s.setInt(1, s2);
+        s.columnDataAddBatch();
+        s.columnDataExecuteBatch();
+        s.columnDataCloseBatch();        
+    }
    @Test(expected = SQLException.class)
    public void createTwoSameDbTest() throws SQLException {
        // when

--- a/src/connector/python/taos/cinterface.py
+++ b/src/connector/python/taos/cinterface.py
@@ -102,9 +102,7 @@ _libtaos.taos_get_client_info.restype = c_char_p
 def taos_get_client_info():
    # type: () -> str
-    """Get client version info.
+    """Get client version info."""
-    获取客户端版本信息。
-    """
    return _libtaos.taos_get_client_info().decode()
@@ -114,6 +112,7 @@ _libtaos.taos_get_server_info.argtypes = (c_void_p,)
 def taos_get_server_info(connection):
    # type: (c_void_p) -> str
+    """Get server version as string."""
    return _libtaos.taos_get_server_info(connection).decode()
@@ -134,11 +133,10 @@ _libtaos.taos_connect.argtypes = c_char_p, c_char_p, c_char_p, c_char_p, c_uint1
 def taos_connect(host=None, user="root", password="taosdata", db=None, port=0):
    # type: (None|str, str, str, None|str, int) -> c_void_p
    """Create TDengine database connection.
-    创建数据库连接，初始化连接上下文。其中需要用户提供的参数包含：
-    - host: server hostname/FQDN, TDengine管理主节点的FQDN
+    - host: server hostname/FQDN
-    - user: user name/用户名
+    - user: user name
-    - password: user password / 用户密码
+    - password: user password
    - db: database name (optional)
    - port: server port
@@ -187,11 +185,10 @@ _libtaos.taos_connect_auth.argtypes = c_char_p, c_char_p, c_char_p, c_char_p, c_
 def taos_connect_auth(host=None, user="root", auth="", db=None, port=0):
    # type: (None|str, str, str, None|str, int) -> c_void_p
-    """
+    """Connect server with auth token.
-    创建数据库连接，初始化连接上下文。其中需要用户提供的参数包含：
-    - host: server hostname/FQDN, TDengine管理主节点的FQDN
+    - host: server hostname/FQDN
-    - user: user name/用户名
+    - user: user name
    - auth: base64 encoded auth token
    - db: database name (optional)
    - port: server port

--- a/src/inc/taosdef.h
+++ b/src/inc/taosdef.h
@@ -164,6 +164,8 @@ do { \
 #define TSDB_RELATION_OR          12
 #define TSDB_RELATION_NOT         13
+#define TSDB_RELATION_MATCH       14
 #define TSDB_BINARY_OP_ADD        30
 #define TSDB_BINARY_OP_SUBTRACT   31
 #define TSDB_BINARY_OP_MULTIPLY   32

--- a/src/inc/ttokendef.h
+++ b/src/inc/ttokendef.h
@@ -37,160 +37,160 @@
 #define TK_NOTNULL                         19
 #define TK_IS                              20
 #define TK_LIKE                            21
-#define TK_GLOB                            22
+#define TK_MATCH                           22
-#define TK_BETWEEN                         23
+#define TK_GLOB                            23
-#define TK_IN                              24
+#define TK_BETWEEN                         24
-#define TK_GT                              25
+#define TK_IN                              25
-#define TK_GE                              26
+#define TK_GT                              26
-#define TK_LT                              27
+#define TK_GE                              27
-#define TK_LE                              28
+#define TK_LT                              28
-#define TK_BITAND                          29
+#define TK_LE                              29
-#define TK_BITOR                           30
+#define TK_BITAND                          30
-#define TK_LSHIFT                          31
+#define TK_BITOR                           31
-#define TK_RSHIFT                          32
+#define TK_LSHIFT                          32
-#define TK_PLUS                            33
+#define TK_RSHIFT                          33
-#define TK_MINUS                           34
+#define TK_PLUS                            34
-#define TK_DIVIDE                          35
+#define TK_MINUS                           35
-#define TK_TIMES                           36
+#define TK_DIVIDE                          36
-#define TK_STAR                            37
+#define TK_TIMES                           37
-#define TK_SLASH                           38
+#define TK_STAR                            38
-#define TK_REM                             39
+#define TK_SLASH                           39
-#define TK_CONCAT                          40
+#define TK_REM                             40
-#define TK_UMINUS                          41
+#define TK_CONCAT                          41
-#define TK_UPLUS                           42
+#define TK_UMINUS                          42
-#define TK_BITNOT                          43
+#define TK_UPLUS                           43
-#define TK_SHOW                            44
+#define TK_BITNOT                          44
-#define TK_DATABASES                       45
+#define TK_SHOW                            45
-#define TK_TOPICS                          46
+#define TK_DATABASES                       46
-#define TK_FUNCTIONS                       47
+#define TK_TOPICS                          47
-#define TK_MNODES                          48
+#define TK_FUNCTIONS                       48
-#define TK_DNODES                          49
+#define TK_MNODES                          49
-#define TK_ACCOUNTS                        50
+#define TK_DNODES                          50
-#define TK_USERS                           51
+#define TK_ACCOUNTS                        51
-#define TK_MODULES                         52
+#define TK_USERS                           52
-#define TK_QUERIES                         53
+#define TK_MODULES                         53
-#define TK_CONNECTIONS                     54
+#define TK_QUERIES                         54
-#define TK_STREAMS                         55
+#define TK_CONNECTIONS                     55
-#define TK_VARIABLES                       56
+#define TK_STREAMS                         56
-#define TK_SCORES                          57
+#define TK_VARIABLES                       57
-#define TK_GRANTS                          58
+#define TK_SCORES                          58
-#define TK_VNODES                          59
+#define TK_GRANTS                          59
-#define TK_DOT                             60
+#define TK_VNODES                          60
-#define TK_CREATE                          61
+#define TK_DOT                             61
-#define TK_TABLE                           62
+#define TK_CREATE                          62
-#define TK_STABLE                          63
+#define TK_TABLE                           63
-#define TK_DATABASE                        64
+#define TK_STABLE                          64
-#define TK_TABLES                          65
+#define TK_DATABASE                        65
-#define TK_STABLES                         66
+#define TK_TABLES                          66
-#define TK_VGROUPS                         67
+#define TK_STABLES                         67
-#define TK_DROP                            68
+#define TK_VGROUPS                         68
-#define TK_TOPIC                           69
+#define TK_DROP                            69
-#define TK_FUNCTION                        70
+#define TK_TOPIC                           70
-#define TK_DNODE                           71
+#define TK_FUNCTION                        71
-#define TK_USER                            72
+#define TK_DNODE                           72
-#define TK_ACCOUNT                         73
+#define TK_USER                            73
-#define TK_USE                             74
+#define TK_ACCOUNT                         74
-#define TK_DESCRIBE                        75
+#define TK_USE                             75
-#define TK_DESC                            76
+#define TK_DESCRIBE                        76
-#define TK_ALTER                           77
+#define TK_DESC                            77
-#define TK_PASS                            78
+#define TK_ALTER                           78
-#define TK_PRIVILEGE                       79
+#define TK_PASS                            79
-#define TK_LOCAL                           80
+#define TK_PRIVILEGE                       80
-#define TK_COMPACT                         81
+#define TK_LOCAL                           81
-#define TK_LP                              82
+#define TK_COMPACT                         82
-#define TK_RP                              83
+#define TK_LP                              83
-#define TK_IF                              84
+#define TK_RP                              84
-#define TK_EXISTS                          85
+#define TK_IF                              85
-#define TK_AS                              86
+#define TK_EXISTS                          86
-#define TK_OUTPUTTYPE                      87
+#define TK_AS                              87
-#define TK_AGGREGATE                       88
+#define TK_OUTPUTTYPE                      88
-#define TK_BUFSIZE                         89
+#define TK_AGGREGATE                       89
-#define TK_PPS                             90
+#define TK_BUFSIZE                         90
-#define TK_TSERIES                         91
+#define TK_PPS                             91
-#define TK_DBS                             92
+#define TK_TSERIES                         92
-#define TK_STORAGE                         93
+#define TK_DBS                             93
-#define TK_QTIME                           94
+#define TK_STORAGE                         94
-#define TK_CONNS                           95
+#define TK_QTIME                           95
-#define TK_STATE                           96
+#define TK_CONNS                           96
-#define TK_COMMA                           97
+#define TK_STATE                           97
-#define TK_KEEP                            98
+#define TK_COMMA                           98
-#define TK_CACHE                           99
+#define TK_KEEP                            99
-#define TK_REPLICA                        100
+#define TK_CACHE                          100
-#define TK_QUORUM                         101
+#define TK_REPLICA                        101
-#define TK_DAYS                           102
+#define TK_QUORUM                         102
-#define TK_MINROWS                        103
+#define TK_DAYS                           103
-#define TK_MAXROWS                        104
+#define TK_MINROWS                        104
-#define TK_BLOCKS                         105
+#define TK_MAXROWS                        105
-#define TK_CTIME                          106
+#define TK_BLOCKS                         106
-#define TK_WAL                            107
+#define TK_CTIME                          107
-#define TK_FSYNC                          108
+#define TK_WAL                            108
-#define TK_COMP                           109
+#define TK_FSYNC                          109
-#define TK_PRECISION                      110
+#define TK_COMP                           110
-#define TK_UPDATE                         111
+#define TK_PRECISION                      111
-#define TK_CACHELAST                      112
+#define TK_UPDATE                         112
-#define TK_PARTITIONS                     113
+#define TK_CACHELAST                      113
-#define TK_UNSIGNED                       114
+#define TK_PARTITIONS                     114
-#define TK_TAGS                           115
+#define TK_UNSIGNED                       115
-#define TK_USING                          116
+#define TK_TAGS                           116
-#define TK_NULL                           117
+#define TK_USING                          117
-#define TK_NOW                            118
+#define TK_NULL                           118
-#define TK_SELECT                         119
+#define TK_NOW                            119
-#define TK_UNION                          120
+#define TK_SELECT                         120
-#define TK_ALL                            121
+#define TK_UNION                          121
-#define TK_DISTINCT                       122
+#define TK_ALL                            122
-#define TK_FROM                           123
+#define TK_DISTINCT                       123
-#define TK_VARIABLE                       124
+#define TK_FROM                           124
-#define TK_INTERVAL                       125
+#define TK_VARIABLE                       125
-#define TK_EVERY                          126
+#define TK_INTERVAL                       126
-#define TK_SESSION                        127
+#define TK_EVERY                          127
-#define TK_STATE_WINDOW                   128
+#define TK_SESSION                        128
-#define TK_FILL                           129
+#define TK_STATE_WINDOW                   129
-#define TK_SLIDING                        130
+#define TK_FILL                           130
-#define TK_ORDER                          131
+#define TK_SLIDING                        131
-#define TK_BY                             132
+#define TK_ORDER                          132
-#define TK_ASC                            133
+#define TK_BY                             133
-#define TK_GROUP                          134
+#define TK_ASC                            134
-#define TK_HAVING                         135
+#define TK_GROUP                          135
-#define TK_LIMIT                          136
+#define TK_HAVING                         136
-#define TK_OFFSET                         137
+#define TK_LIMIT                          137
-#define TK_SLIMIT                         138
+#define TK_OFFSET                         138
-#define TK_SOFFSET                        139
+#define TK_SLIMIT                         139
-#define TK_WHERE                          140
+#define TK_SOFFSET                        140
-#define TK_RESET                          141
+#define TK_WHERE                          141
-#define TK_QUERY                          142
+#define TK_RESET                          142
-#define TK_SYNCDB                         143
+#define TK_QUERY                          143
-#define TK_ADD                            144
+#define TK_SYNCDB                         144
-#define TK_COLUMN                         145
+#define TK_ADD                            145
-#define TK_MODIFY                         146
+#define TK_COLUMN                         146
-#define TK_TAG                            147
+#define TK_MODIFY                         147
-#define TK_CHANGE                         148
+#define TK_TAG                            148
-#define TK_SET                            149
+#define TK_CHANGE                         149
-#define TK_KILL                           150
+#define TK_SET                            150
-#define TK_CONNECTION                     151
+#define TK_KILL                           151
-#define TK_STREAM                         152
+#define TK_CONNECTION                     152
-#define TK_COLON                          153
+#define TK_STREAM                         153
-#define TK_ABORT                          154
+#define TK_COLON                          154
-#define TK_AFTER                          155
+#define TK_ABORT                          155
-#define TK_ATTACH                         156
+#define TK_AFTER                          156
-#define TK_BEFORE                         157
+#define TK_ATTACH                         157
-#define TK_BEGIN                          158
+#define TK_BEFORE                         158
-#define TK_CASCADE                        159
+#define TK_BEGIN                          159
-#define TK_CLUSTER                        160
+#define TK_CASCADE                        160
-#define TK_CONFLICT                       161
+#define TK_CLUSTER                        161
-#define TK_COPY                           162
+#define TK_CONFLICT                       162
-#define TK_DEFERRED                       163
+#define TK_COPY                           163
-#define TK_DELIMITERS                     164
+#define TK_DEFERRED                       164
-#define TK_DETACH                         165
+#define TK_DELIMITERS                     165
-#define TK_EACH                           166
+#define TK_DETACH                         166
-#define TK_END                            167
+#define TK_EACH                           167
-#define TK_EXPLAIN                        168
+#define TK_END                            168
-#define TK_FAIL                           169
+#define TK_EXPLAIN                        169
-#define TK_FOR                            170
+#define TK_FAIL                           170
-#define TK_IGNORE                         171
+#define TK_FOR                            171
-#define TK_IMMEDIATE                      172
+#define TK_IGNORE                         172
-#define TK_INITIALLY                      173
+#define TK_IMMEDIATE                      173
-#define TK_INSTEAD                        174
+#define TK_INITIALLY                      174
-#define TK_MATCH                          175
+#define TK_INSTEAD                        175
 #define TK_KEY                            176
 #define TK_OF                             177
 #define TK_RAISE                          178

--- a/src/kit/taosdemo/taosdemo.c
+++ b/src/kit/taosdemo/taosdemo.c
--- a/src/plugins/http/src/httpJson.c
+++ b/src/plugins/http/src/httpJson.c
@@ -272,26 +272,35 @@ void httpJsonTimestamp(JsonBuf* buf, int64_t t, int32_t timePrecision) {
  switch (timePrecision) {
    case TSDB_TIME_PRECISION_MILLI: {
+      mod = ((t) % 1000 + 1000) % 1000;
+      if (t < 0 && mod != 0) {
+        t -= 1000;
+      }
      quot = t / 1000;
      fractionLen = 5;
      format = ".%03" PRId64;
-      mod = t % 1000;
      break;
    }
    case TSDB_TIME_PRECISION_MICRO: {
+      mod = ((t) % 1000000 + 1000000) % 1000000;
+      if (t < 0 && mod != 0) {
+        t -= 1000000;
+      }
      quot = t / 1000000;
      fractionLen = 8;
      format = ".%06" PRId64;
-      mod = t % 1000000;
      break;
    }
    case TSDB_TIME_PRECISION_NANO: {
+      mod = ((t) % 1000000000 + 1000000000) % 1000000000;
+      if (t < 0 && mod != 0) {
+        t -= 1000000000;
+      }
      quot = t / 1000000000;
      fractionLen = 11;
      format = ".%09" PRId64;
-      mod = t % 1000000000;
      break;
    }
@@ -319,26 +328,35 @@ void httpJsonUtcTimestamp(JsonBuf* buf, int64_t t, int32_t timePrecision) {
  switch (timePrecision) {
    case TSDB_TIME_PRECISION_MILLI: {
+      mod = ((t) % 1000 + 1000) % 1000;
+      if (t < 0 && mod != 0) {
+        t -= 1000;
+      }
      quot = t / 1000;
      fractionLen = 5;
      format = ".%03" PRId64;
-      mod = t % 1000;
      break;
    }
    case TSDB_TIME_PRECISION_MICRO: {
+      mod = ((t) % 1000000 + 1000000) % 1000000;
+      if (t < 0 && mod != 0) {
+        t -= 1000000;
+      }
      quot = t / 1000000;
      fractionLen = 8;
      format = ".%06" PRId64;
-      mod = t % 1000000;
      break;
    }
    case TSDB_TIME_PRECISION_NANO: {
+      mod = ((t) % 1000000000 + 1000000000) % 1000000000;
+      if (t < 0 && mod != 0) {
+        t -= 1000000000;
+      }
      quot = t / 1000000000;
      fractionLen = 11;
      format = ".%09" PRId64;
-      mod = t % 1000000000;
      break;
    }

--- a/src/query/inc/sql.y
+++ b/src/query/inc/sql.y
@@ -11,7 +11,7 @@
 %left OR.
 %left AND.
 %right NOT.
-%left EQ NE ISNULL NOTNULL IS LIKE GLOB BETWEEN IN.
+%left EQ NE ISNULL NOTNULL IS LIKE MATCH GLOB BETWEEN IN.
 %left GT GE LT LE.
 %left BITAND BITOR LSHIFT RSHIFT.
 %left PLUS MINUS.
@@ -751,6 +751,9 @@ expr(A) ::= expr(X) REM   expr(Y).   {A = tSqlExprCreate(X, Y, TK_REM);   }
 // like expression
 expr(A) ::= expr(X) LIKE expr(Y).    {A = tSqlExprCreate(X, Y, TK_LIKE);  }
+// match expression
+expr(A) ::= expr(X) MATCH expr(Y).    {A = tSqlExprCreate(X, Y, TK_MATCH);  }
 //in expression
 expr(A) ::= expr(X) IN LP exprlist(Y) RP.   {A = tSqlExprCreate(X, (tSqlExpr*)Y, TK_IN); }

--- a/src/query/src/qExecutor.c
+++ b/src/query/src/qExecutor.c
@@ -6388,6 +6388,19 @@ static SSDataBlock* hashGroupbyAggregate(void* param, bool* newgroup) {
  return pInfo->binfo.pRes;
 }
+static void doHandleRemainBlockForNewGroupImpl(SFillOperatorInfo *pInfo, SQueryRuntimeEnv* pRuntimeEnv, bool* newgroup) {
+  pInfo->totalInputRows = pInfo->existNewGroupBlock->info.rows;
+  int64_t ekey = Q_STATUS_EQUAL(pRuntimeEnv->status, QUERY_COMPLETED)?pRuntimeEnv->pQueryAttr->window.ekey:pInfo->existNewGroupBlock->info.window.ekey;
+  taosResetFillInfo(pInfo->pFillInfo, pInfo->pFillInfo->start);
+  taosFillSetStartInfo(pInfo->pFillInfo, pInfo->existNewGroupBlock->info.rows, ekey);
+  taosFillSetInputDataBlock(pInfo->pFillInfo, pInfo->existNewGroupBlock);
+  doFillTimeIntervalGapsInResults(pInfo->pFillInfo, pInfo->pRes, pRuntimeEnv->resultInfo.capacity, pInfo->p);
+  pInfo->existNewGroupBlock = NULL;
+  *newgroup = true;
+}
 static void doHandleRemainBlockFromNewGroup(SFillOperatorInfo *pInfo, SQueryRuntimeEnv  *pRuntimeEnv, bool *newgroup) {
  if (taosFillHasMoreResults(pInfo->pFillInfo)) {
    *newgroup = false;
@@ -6399,16 +6412,7 @@ static void doHandleRemainBlockFromNewGroup(SFillOperatorInfo *pInfo, SQueryRunt
  // handle the cached new group data block
  if (pInfo->existNewGroupBlock) {
-    pInfo->totalInputRows = pInfo->existNewGroupBlock->info.rows;
+    doHandleRemainBlockForNewGroupImpl(pInfo, pRuntimeEnv, newgroup);
-    int64_t ekey = Q_STATUS_EQUAL(pRuntimeEnv->status, QUERY_COMPLETED)?pRuntimeEnv->pQueryAttr->window.ekey:pInfo->existNewGroupBlock->info.window.ekey;
-    taosResetFillInfo(pInfo->pFillInfo, pInfo->pFillInfo->start);
-    taosFillSetStartInfo(pInfo->pFillInfo, pInfo->existNewGroupBlock->info.rows, ekey);
-    taosFillSetInputDataBlock(pInfo->pFillInfo, pInfo->existNewGroupBlock);
-    doFillTimeIntervalGapsInResults(pInfo->pFillInfo, pInfo->pRes, pRuntimeEnv->resultInfo.capacity, pInfo->p);
-    pInfo->existNewGroupBlock = NULL;
-    *newgroup = true;
  }
 }
@@ -6427,26 +6431,6 @@ static SSDataBlock* doFill(void* param, bool* newgroup) {
  if (pInfo->pRes->info.rows > pRuntimeEnv->resultInfo.threshold || (!pInfo->multigroupResult && pInfo->pRes->info.rows > 0)) {
    return pInfo->pRes;
  }
-//  if (taosFillHasMoreResults(pInfo->pFillInfo)) {
-//    *newgroup = false;
-//    doFillTimeIntervalGapsInResults(pInfo->pFillInfo, pInfo->pRes, (int32_t)pRuntimeEnv->resultInfo.capacity);
-//    return pInfo->pRes;
-//  }
-//
-//  // handle the cached new group data block
-//  if (pInfo->existNewGroupBlock) {
-//    pInfo->totalInputRows = pInfo->existNewGroupBlock->info.rows;
-//    int64_t ekey = Q_STATUS_EQUAL(pRuntimeEnv->status, QUERY_COMPLETED)?pRuntimeEnv->pQueryAttr->window.ekey:pInfo->existNewGroupBlock->info.window.ekey;
-//    taosResetFillInfo(pInfo->pFillInfo, pInfo->pFillInfo->start);
-//
-//    taosFillSetStartInfo(pInfo->pFillInfo, pInfo->existNewGroupBlock->info.rows, ekey);
-//    taosFillSetInputDataBlock(pInfo->pFillInfo, pInfo->existNewGroupBlock);
-//
-//    doFillTimeIntervalGapsInResults(pInfo->pFillInfo, pInfo->pRes, pRuntimeEnv->resultInfo.capacity);
-//    pInfo->existNewGroupBlock = NULL;
-//    *newgroup = true;
-//    return (pInfo->pRes->info.rows > 0)? pInfo->pRes:NULL;
-//  }
  while(1) {
    publishOperatorProfEvent(pOperator->upstream[0], QUERY_PROF_BEFORE_OPERATOR_EXEC);
@@ -6493,46 +6477,13 @@ static SSDataBlock* doFill(void* param, bool* newgroup) {
      if (pInfo->pRes->info.rows > pRuntimeEnv->resultInfo.threshold || pBlock == NULL) {
        return pInfo->pRes;
      }
-//      if (taosFillHasMoreResults(pInfo->pFillInfo)) {
-//        *newgroup = false;
-//        doFillTimeIntervalGapsInResults(pInfo->pFillInfo, pInfo->pRes, (int32_t)pRuntimeEnv->resultInfo.capacity);
-//        return pInfo->pRes;
-//      }
-//
-//      // handle the cached new group data block
-//      if (pInfo->existNewGroupBlock) {
-//        pInfo->totalInputRows = pInfo->existNewGroupBlock->info.rows;
-//        int64_t ekey = Q_STATUS_EQUAL(pRuntimeEnv->status, QUERY_COMPLETED)?pRuntimeEnv->pQueryAttr->window.ekey:pInfo->existNewGroupBlock->info.window.ekey;
-//        taosResetFillInfo(pInfo->pFillInfo, pInfo->pFillInfo->start);
-//
-//        taosFillSetStartInfo(pInfo->pFillInfo, pInfo->existNewGroupBlock->info.rows, ekey);
-//        taosFillSetInputDataBlock(pInfo->pFillInfo, pInfo->existNewGroupBlock);
-//
-//        doFillTimeIntervalGapsInResults(pInfo->pFillInfo, pInfo->pRes, pRuntimeEnv->resultInfo.capacity);
-//        pInfo->existNewGroupBlock = NULL;
-//        *newgroup = true;
-//
-//        if (pInfo->pRes->info.rows > pRuntimeEnv->resultInfo.threshold) {
-//          return pInfo->pRes;
-//        }
-//
-////        return (pInfo->pRes->info.rows > 0)? pInfo->pRes:NULL;
-//      }
    } else if (pInfo->existNewGroupBlock) {  // try next group
-      pInfo->totalInputRows = pInfo->existNewGroupBlock->info.rows;
+      assert(pBlock != NULL);
-      int64_t ekey = pInfo->existNewGroupBlock->info.window.ekey;
+      doHandleRemainBlockForNewGroupImpl(pInfo, pRuntimeEnv, newgroup);
-      taosResetFillInfo(pInfo->pFillInfo, pInfo->pFillInfo->start);
-      taosFillSetStartInfo(pInfo->pFillInfo, pInfo->existNewGroupBlock->info.rows, ekey);
-      taosFillSetInputDataBlock(pInfo->pFillInfo, pInfo->existNewGroupBlock);
-      doFillTimeIntervalGapsInResults(pInfo->pFillInfo, pInfo->pRes, pRuntimeEnv->resultInfo.capacity, pInfo->p);
-      pInfo->existNewGroupBlock = NULL;
-      *newgroup = true;
-      return (pInfo->pRes->info.rows > 0) ? pInfo->pRes : NULL;
+      if (pInfo->pRes->info.rows > pRuntimeEnv->resultInfo.threshold) {
+        return pInfo->pRes;
+      }
    } else {
      return NULL;
    }

--- a/src/query/src/qFilter.c
+++ b/src/query/src/qFilter.c
@@ -28,6 +28,7 @@ OptrStr gOptrStr[] = {
  {TSDB_RELATION_GREATER_EQUAL,            ">="},
  {TSDB_RELATION_NOT_EQUAL,                "!="},
  {TSDB_RELATION_LIKE,                     "like"},
+  {TSDB_RELATION_MATCH,                    "match"},
  {TSDB_RELATION_ISNULL,                   "is null"},
  {TSDB_RELATION_NOTNULL,                  "not null"},
  {TSDB_RELATION_IN,                       "in"},
@@ -156,7 +157,7 @@ int8_t filterGetRangeCompFuncFromOptrs(uint8_t optr, uint8_t optr2) {
 __compar_fn_t gDataCompare[] = {compareInt32Val, compareInt8Val, compareInt16Val, compareInt64Val, compareFloatVal,
  compareDoubleVal, compareLenPrefixedStr, compareStrPatternComp, compareFindItemInSet, compareWStrPatternComp, 
  compareLenPrefixedWStr, compareUint8Val, compareUint16Val, compareUint32Val, compareUint64Val,
-  setCompareBytes1, setCompareBytes2, setCompareBytes4, setCompareBytes8
+  setCompareBytes1, setCompareBytes2, setCompareBytes4, setCompareBytes8, compareStrRegexComp,
 };
 int8_t filterGetCompFuncIdx(int32_t type, int32_t optr) {
@@ -195,7 +196,9 @@ int8_t filterGetCompFuncIdx(int32_t type, int32_t optr) {
    case TSDB_DATA_TYPE_FLOAT:     comparFn = 4;  break;
    case TSDB_DATA_TYPE_DOUBLE:    comparFn = 5; break;
    case TSDB_DATA_TYPE_BINARY: {
-      if (optr == TSDB_RELATION_LIKE) { /* wildcard query using like operator */
+      if (optr == TSDB_RELATION_MATCH) {
+        comparFn = 19;
+      } else if (optr == TSDB_RELATION_LIKE) { /* wildcard query using like operator */
        comparFn = 7;
      } else if (optr == TSDB_RELATION_IN) {
        comparFn = 8;
@@ -207,7 +210,9 @@ int8_t filterGetCompFuncIdx(int32_t type, int32_t optr) {
    }
    case TSDB_DATA_TYPE_NCHAR: {
-      if (optr == TSDB_RELATION_LIKE) {
+      if (optr == TSDB_RELATION_MATCH) {
+        comparFn = 19;
+      } else if (optr == TSDB_RELATION_LIKE) {
        comparFn = 9;
      } else if (optr == TSDB_RELATION_IN) {
        comparFn = 8;
@@ -1871,6 +1876,9 @@ bool filterDoCompare(__compar_fn_t func, uint8_t optr, void *left, void *right)
    case TSDB_RELATION_LIKE: {
      return ret == 0;
    }
+    case TSDB_RELATION_MATCH: {
+      return ret == 0;
+    }
    case TSDB_RELATION_IN: {
      return ret == 1;
    }
@@ -2641,7 +2649,7 @@ int32_t filterRmUnitByRange(SFilterInfo *info, SDataStatis *pDataStatis, int32_t
    }
    if (cunit->optr == TSDB_RELATION_ISNULL || cunit->optr == TSDB_RELATION_NOTNULL 
-     || cunit->optr == TSDB_RELATION_IN || cunit->optr == TSDB_RELATION_LIKE
+     || cunit->optr == TSDB_RELATION_IN || cunit->optr == TSDB_RELATION_LIKE || cunit->optr == TSDB_RELATION_MATCH
     || cunit->optr == TSDB_RELATION_NOT_EQUAL) {
      continue;
    }

--- a/src/query/src/sql.c
+++ b/src/query/src/sql.c
--- a/src/tsdb/src/tsdbCommit.c
+++ b/src/tsdb/src/tsdbCommit.c
@@ -1418,13 +1418,11 @@ static void tsdbLoadAndMergeFromCache(SDataCols *pDataCols, int *iter, SCommitIt
  while (true) {
    key1 = (*iter >= pDataCols->numOfRows) ? INT64_MAX : dataColsKeyAt(pDataCols, *iter);
-    bool isRowDel = false;
    SMemRow row = tsdbNextIterRow(pCommitIter->pIter);
    if (row == NULL || memRowKey(row) > maxKey) {
      key2 = INT64_MAX;
    } else {
      key2 = memRowKey(row);
-      isRowDel = memRowDeleted(row);
    }
    if (key1 == INT64_MAX && key2 == INT64_MAX) break;
@@ -1439,36 +1437,33 @@ static void tsdbLoadAndMergeFromCache(SDataCols *pDataCols, int *iter, SCommitIt
      pTarget->numOfRows++;
      (*iter)++;
    } else if (key1 > key2) {
-      if (!isRowDel) {
+      if (pSchema == NULL || schemaVersion(pSchema) != memRowVersion(row)) {
-        if (pSchema == NULL || schemaVersion(pSchema) != memRowVersion(row)) {
+        pSchema = tsdbGetTableSchemaImpl(pCommitIter->pTable, false, false, memRowVersion(row));
-          pSchema = tsdbGetTableSchemaImpl(pCommitIter->pTable, false, false, memRowVersion(row));
+        ASSERT(pSchema != NULL);
-          ASSERT(pSchema != NULL);
-        }
-        tdAppendMemRowToDataCol(row, pSchema, pTarget, true);
      }
+      tdAppendMemRowToDataCol(row, pSchema, pTarget, true);
      tSkipListIterNext(pCommitIter->pIter);
    } else {
-      if (update) {
+      if (update != TD_ROW_OVERWRITE_UPDATE) {
-        if (!isRowDel) {
+        //copy disk data
-          if (pSchema == NULL || schemaVersion(pSchema) != memRowVersion(row)) {
-            pSchema = tsdbGetTableSchemaImpl(pCommitIter->pTable, false, false, memRowVersion(row));
-            ASSERT(pSchema != NULL);
-          }
-          tdAppendMemRowToDataCol(row, pSchema, pTarget, update == TD_ROW_OVERWRITE_UPDATE);
-        }
-      } else {
-        ASSERT(!isRowDel);
        for (int i = 0; i < pDataCols->numOfCols; i++) {
          //TODO: dataColAppendVal may fail
          dataColAppendVal(pTarget->cols + i, tdGetColDataOfRow(pDataCols->cols + i, *iter), pTarget->numOfRows,
                           pTarget->maxPoints);
        }
-        pTarget->numOfRows++;
+        if(update == TD_ROW_DISCARD_UPDATE) pTarget->numOfRows++;
+      }
+      if (update != TD_ROW_DISCARD_UPDATE) {
+        //copy mem data
+        if (pSchema == NULL || schemaVersion(pSchema) != memRowVersion(row)) {
+          pSchema = tsdbGetTableSchemaImpl(pCommitIter->pTable, false, false, memRowVersion(row));
+          ASSERT(pSchema != NULL);
+        }
+        tdAppendMemRowToDataCol(row, pSchema, pTarget, update == TD_ROW_OVERWRITE_UPDATE);
      }
      (*iter)++;
      tSkipListIterNext(pCommitIter->pIter);

--- a/src/tsdb/src/tsdbRead.c
+++ b/src/tsdb/src/tsdbRead.c
@@ -3709,6 +3709,9 @@ static bool tableFilterFp(const void* pNode, void* param) {
    case TSDB_RELATION_LIKE: {
      return ret == 0;
    }
+    case TSDB_RELATION_MATCH: {
+      return ret == 0;
+    }
    case TSDB_RELATION_IN: {
      return ret == 1;
    }
@@ -4042,6 +4045,8 @@ static int32_t setQueryCond(tQueryInfo *queryColInfo, SQueryCond* pCond) {
    pCond->start->v    = queryColInfo->q; 
  } else if (optr == TSDB_RELATION_LIKE) {
    assert(0);
+  } else if (optr == TSDB_RELATION_MATCH) {
+    assert(0);
  }
  return TSDB_CODE_SUCCESS;
@@ -4199,7 +4204,7 @@ static void queryIndexlessColumn(SSkipList* pSkipList, tQueryInfo* pQueryInfo, S
    if (pQueryInfo->sch.colId == TSDB_TBNAME_COLUMN_INDEX) {
      if (pQueryInfo->optr == TSDB_RELATION_IN) {
        addToResult = pQueryInfo->compare(name, pQueryInfo->q);
-      } else if (pQueryInfo->optr == TSDB_RELATION_LIKE) {
+      } else if (pQueryInfo->optr == TSDB_RELATION_LIKE || pQueryInfo->optr == TSDB_RELATION_MATCH) {
        addToResult = !pQueryInfo->compare(name, pQueryInfo->q);
      }
    } else {
@@ -4231,7 +4236,8 @@ void getTableListfromSkipList(tExprNode *pExpr, SSkipList *pSkipList, SArray *re
    param->setupInfoFn(pExpr, param->pExtInfo);
    tQueryInfo *pQueryInfo = pExpr->_node.info;
-    if (pQueryInfo->indexed && (pQueryInfo->optr != TSDB_RELATION_LIKE && pQueryInfo->optr != TSDB_RELATION_IN)) {
+    if (pQueryInfo->indexed && (pQueryInfo->optr != TSDB_RELATION_LIKE && pQueryInfo->optr != TSDB_RELATION_MATCH
+                                && pQueryInfo->optr != TSDB_RELATION_IN)) {
      queryIndexedColumn(pSkipList, pQueryInfo, result);
    } else {
      queryIndexlessColumn(pSkipList, pQueryInfo, result, param->nodeFilterFn);

--- a/src/util/inc/tcompare.h
+++ b/src/util/inc/tcompare.h
@@ -22,10 +22,11 @@ extern "C" {
 #include "os.h"
-#define TSDB_PATTERN_MATCH               0
+#define TSDB_PATTERN_MATCH 0
-#define TSDB_PATTERN_NOMATCH             1
+#define TSDB_PATTERN_NOMATCH 1
-#define TSDB_PATTERN_NOWILDCARDMATCH     2
+#define TSDB_PATTERN_NOWILDCARDMATCH 2
-#define TSDB_PATTERN_STRING_DEFAULT_LEN  100
+#define TSDB_PATTERN_STRING_DEFAULT_LEN 100
+#define TSDB_REGEX_STRING_DEFAULT_LEN 128
 #define FLT_COMPAR_TOL_FACTOR    4
 #define FLT_EQUAL(_x, _y)        (fabs((_x) - (_y)) <= (FLT_COMPAR_TOL_FACTOR * FLT_EPSILON))
@@ -82,6 +83,7 @@ int32_t compareLenPrefixedStr(const void *pLeft, const void *pRight);
 int32_t compareLenPrefixedWStr(const void *pLeft, const void *pRight);
 int32_t compareStrPatternComp(const void* pLeft, const void* pRight);
+int32_t compareStrRegexComp(const void* pLeft, const void* pRight);
 int32_t compareFindItemInSet(const void *pLeft, const void* pRight);
 int32_t compareWStrPatternComp(const void* pLeft, const void* pRight);

--- a/src/util/src/tarray.c
+++ b/src/util/src/tarray.c
@@ -112,14 +112,15 @@ void taosArrayRemoveBatch(SArray *pArray, const int32_t* pData, int32_t numOfEle
    i += 1;
  }
-  assert(i == pData[numOfElems - 1] + 1);
+  assert(i == pData[numOfElems - 1] + 1 && i <= size);
-  int32_t dstIndex = pData[numOfElems - 1] - numOfElems + 1;
  int32_t srcIndex = pData[numOfElems - 1] + 1;
+  int32_t dstIndex = pData[numOfElems - 1] - numOfElems + 1;
-  char* dst = TARRAY_GET_ELEM(pArray, dstIndex);
+  if (pArray->size - srcIndex > 0) {
-  char* src = TARRAY_GET_ELEM(pArray, srcIndex);
+    char* dst = TARRAY_GET_ELEM(pArray, dstIndex);
-  memmove(dst, src, pArray->elemSize * (pArray->size - numOfElems));
+    char* src = TARRAY_GET_ELEM(pArray, srcIndex);
+    memmove(dst, src, pArray->elemSize * (pArray->size - srcIndex));
+  }
  pArray->size -= numOfElems;
 }

--- a/src/util/src/tcache.c
+++ b/src/util/src/tcache.c
@@ -71,6 +71,8 @@ static pthread_once_t cacheThreadInit = PTHREAD_ONCE_INIT;
 static pthread_mutex_t guard          = PTHREAD_MUTEX_INITIALIZER;
 static SArray* pCacheArrayList        = NULL;
 static bool    stopRefreshWorker      = false;
+static bool    refreshWorkerNormalStopped       = false;
+static bool    refreshWorkerUnexpectedStopped   = false;
 static void doInitRefreshThread(void) {
  pCacheArrayList = taosArrayInit(4, POINTER_BYTES);
@@ -537,8 +539,10 @@ void taosCacheCleanup(SCacheObj *pCacheObj) {
  pCacheObj->deleting = 1;
  // wait for the refresh thread quit before destroying the cache object.
-  // But in the dll, the child thread will be killed before atexit takes effect.So here we only wait for 2 seconds.
+  // But in the dll, the child thread will be killed before atexit takes effect.
-  for (int i = 0; i < 40&&atomic_load_8(&pCacheObj->deleting) != 0; i++) {
+  while(atomic_load_8(&pCacheObj->deleting) != 0) {
+    if (refreshWorkerNormalStopped) break;    
+    if (refreshWorkerUnexpectedStopped) return;    
    taosMsleep(50);
  }
@@ -677,6 +681,12 @@ static void doCacheRefresh(SCacheObj* pCacheObj, int64_t time, __cache_free_fn_t
  taosHashCondTraverse(pCacheObj->pHashTable, travHashTableFn, &sup);
 }
+void taosCacheRefreshWorkerUnexpectedStopped(void) {
+  if(!refreshWorkerNormalStopped) {
+    refreshWorkerUnexpectedStopped=true;
+  }
+}
 void* taosCacheTimedRefresh(void *handle) {
  assert(pCacheArrayList != NULL);
  uDebug("cache refresh thread starts");
@@ -685,6 +695,7 @@ void* taosCacheTimedRefresh(void *handle) {
  const int32_t SLEEP_DURATION = 500; //500 ms
  int64_t count = 0;
+  atexit(taosCacheRefreshWorkerUnexpectedStopped);
  while(1) {
    taosMsleep(SLEEP_DURATION);
@@ -749,6 +760,7 @@ void* taosCacheTimedRefresh(void *handle) {
  pCacheArrayList = NULL;
  pthread_mutex_destroy(&guard);
+  refreshWorkerNormalStopped=true;
  uDebug("cache refresh thread quits");
  return NULL;
@@ -763,6 +775,6 @@ void taosCacheRefresh(SCacheObj *pCacheObj, __cache_free_fn_t fp) {
  doCacheRefresh(pCacheObj, now, fp);
 }
-void taosStopCacheRefreshWorker() {
+void taosStopCacheRefreshWorker(void) {
-  stopRefreshWorker = false;
+  stopRefreshWorker = true;
 }
\ No newline at end of file
--- a/src/util/src/tcompare.c
+++ b/src/util/src/tcompare.c
@@ -12,11 +12,17 @@
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
+#define _BSD_SOURCE
+#define _GNU_SOURCE
+#define _XOPEN_SOURCE
+#define _DEFAULT_SOURCE
-#include "os.h"
-#include "ttype.h"
 #include "tcompare.h"
+#include "tulog.h"
 #include "hash.h"
+#include "regex.h"
+#include "os.h"
+#include "ttype.h"
 int32_t setCompareBytes1(const void *pLeft, const void *pRight) {
  return NULL != taosHashGet((SHashObj *)pRight, pLeft, 1) ? 1 : 0;
@@ -344,6 +350,43 @@ int32_t compareStrPatternComp(const void* pLeft, const void* pRight) {
  return (ret == TSDB_PATTERN_MATCH) ? 0 : 1;
 }
+int32_t compareStrRegexComp(const void* pLeft, const void* pRight) {
+  size_t sz = varDataLen(pRight);
+  char *pattern = malloc(sz + 1);
+  memcpy(pattern, varDataVal(pRight), varDataLen(pRight));
+  pattern[sz] = 0;
+  sz = varDataLen(pLeft);
+  char *str = malloc(sz + 1);
+  memcpy(str, varDataVal(pLeft), sz);
+  str[sz] = 0;
+  int errCode = 0;
+  regex_t regex;
+  char    msgbuf[256] = {0};
+  int cflags = REG_EXTENDED;
+  if ((errCode = regcomp(&regex, pattern, cflags)) != 0) {
+    regerror(errCode, &regex, msgbuf, sizeof(msgbuf));
+    uError("Failed to compile regex pattern %s. reason %s", pattern, msgbuf);
+    regfree(&regex);
+    free(str);
+    free(pattern);
+    return 1;
+  }
+  errCode = regexec(&regex, str, 0, NULL, 0);
+  if (errCode != 0 && errCode != REG_NOMATCH) {
+    regerror(errCode, &regex, msgbuf, sizeof(msgbuf));
+    uDebug("Failed to match %s with pattern %s, reason %s", str, pattern, msgbuf)
+  }
+  int32_t result = (errCode == 0) ? 0 : 1;
+  regfree(&regex);
+  free(str);
+  free(pattern);
+  return result;
+}
 int32_t taosArrayCompareString(const void* a, const void* b) {
  const char* x = *(const char**)a;
  const char* y = *(const char**)b;
@@ -405,7 +448,9 @@ __compar_fn_t getComparFunc(int32_t type, int32_t optr) {
    case TSDB_DATA_TYPE_FLOAT:     comparFn = compareFloatVal;  break;
    case TSDB_DATA_TYPE_DOUBLE:    comparFn = compareDoubleVal; break;
    case TSDB_DATA_TYPE_BINARY: {
-      if (optr == TSDB_RELATION_LIKE) { /* wildcard query using like operator */
+      if (optr == TSDB_RELATION_MATCH) {
+        comparFn = compareStrRegexComp;
+      } else if (optr == TSDB_RELATION_LIKE) { /* wildcard query using like operator */
        comparFn = compareStrPatternComp;
      } else if (optr == TSDB_RELATION_IN) {
        comparFn = compareFindItemInSet;
@@ -417,7 +462,9 @@ __compar_fn_t getComparFunc(int32_t type, int32_t optr) {
    }
    case TSDB_DATA_TYPE_NCHAR: {
-      if (optr == TSDB_RELATION_LIKE) {
+      if (optr == TSDB_RELATION_MATCH) {
+        comparFn = compareStrRegexComp;
+      } else if (optr == TSDB_RELATION_LIKE) {
        comparFn = compareWStrPatternComp;
      } else if (optr == TSDB_RELATION_IN) {
        comparFn = compareFindItemInSet;

--- a/src/util/src/tsocket.c
+++ b/src/util/src/tsocket.c
@@ -488,7 +488,7 @@ SOCKET taosOpenTcpServerSocket(uint32_t ip, uint16_t port) {
    return -1;
  }
-  if (listen(sockFd, 10) < 0) {
+  if (listen(sockFd, 1024) < 0) {
    uError("listen tcp server socket failed, 0x%x:%hu(%s)", ip, port, strerror(errno));
    taosCloseSocket(sockFd);
    return -1;

--- a/src/util/src/ttokenizer.c
+++ b/src/util/src/ttokenizer.c
@@ -53,6 +53,7 @@ static SKeyword keywordTable[] = {
    {"NOTNULL",      TK_NOTNULL},
    {"IS",           TK_IS},
    {"LIKE",         TK_LIKE},
+    {"MATCH",        TK_MATCH},
    {"GLOB",         TK_GLOB},
    {"BETWEEN",      TK_BETWEEN},
    {"IN",           TK_IN},

--- a/tests/examples/nodejs/test1970.js
+++ b/tests/examples/nodejs/test1970.js
+const taos = require('td2.0-connector');
+var conn = taos.connect({host:"127.0.0.1", user:"root", password:"taosdata", config:"/etc/taos",port:0})
+var c1 = conn.cursor(); // Initializing a new cursor
+let stime = new Date();
+let interval = 1000;
+function convertDateToTS(date) {
+  let tsArr = date.toISOString().split("T")
+  return "\"" + tsArr[0] + " " + tsArr[1].substring(0, tsArr[1].length - 1) + "\"";
+}
+function R(l, r) {
+  return Math.random() * (r - l) - r;
+}
+function randomBool() {
+  if (Math.random() < 0.5) {
+    return true;
+  }
+  return false;
+}
+// Initialize
+const dbname = "nodejs_1970_db";
+const tbname = "t1";
+let dropDB = "drop database if exists " + dbname
+console.log(dropDB);//asdasdasd
+c1.execute(dropDB);///asdasd
+let createDB = "create database  " + dbname + " keep 36500"
+console.log(createDB);
+c1.execute(createDB);
+let useTbl = "use " + dbname
+console.log(useTbl)
+c1.execute(useTbl);
+let createTbl = "create table if not exists " + tbname + "(ts timestamp,id int)"
+console.log(createTbl);
+c1.execute(createTbl);
+//1969-12-31 23:59:59.999
+//1970-01-01 00:00:00.000
+//1970-01-01 07:59:59.999
+//1970-01-01 08:00:00.000a
+//1628928479484  2021-08-14 08:07:59.484
+let sql1 = "insert into " + dbname + "." + tbname + " values('1969-12-31 23:59:59.999',1)"
+console.log(sql1);
+c1.execute(sql1);
+let sql2 = "insert into " + dbname + "." + tbname + " values('1970-01-01 00:00:00.000',2)"
+console.log(sql2);
+c1.execute(sql2);
+let sql3 = "insert into " + dbname + "." + tbname + " values('1970-01-01 07:59:59.999',3)"
+console.log(sql3);
+c1.execute(sql3);
+let sql4 = "insert into " + dbname + "." + tbname + " values('1970-01-01 08:00:00.000',4)"
+console.log(sql4);
+c1.execute(sql4);
+let sql5 = "insert into " + dbname + "." + tbname + " values('2021-08-14 08:07:59.484',5)"
+console.log(sql5);
+c1.execute(sql5);
+// Select
+let query1 = "select * from " + dbname + "." + tbname
+console.log(query1);
+c1.execute(query1);
+var d = c1.fetchall();
+console.log(c1.fields);
+for (let i = 0; i < d.length; i++)
+  console.log(d[i][0].valueOf());
+//initialize
+let initSql1 = "drop table if exists " + tbname
+console.log(initSql1);
+c1.execute(initSql1);
+console.log(createTbl);
+c1.execute(createTbl);
+c1.execute(useTbl)
+//-28800001 1969-12-31 23:59:59.999
+//-28800000 1970-01-01 00:00:00.000
+//-1 1970-01-01 07:59:59.999
+//0  1970-01-01 08:00:00.00
+//1628928479484  2021-08-14 08:07:59.484
+let sql11 = "insert into " + dbname + "." + tbname + " values(-28800001,11)";
+console.log(sql11);
+c1.execute(sql11);
+let sql12 = "insert into " + dbname + "." + tbname + " values(-28800000,12)"
+console.log(sql12);
+c1.execute(sql12);
+let sql13 = "insert into " + dbname + "." + tbname + " values(-1,13)"
+console.log(sql13);
+c1.execute(sql13);
+let sql14 = "insert into " + dbname + "." + tbname + " values(0,14)"
+console.log(sql14);
+c1.execute(sql14);
+let sql15 = "insert into " + dbname + "." + tbname + " values(1628928479484,15)"
+console.log(sql15);
+c1.execute(sql15);
+// Select
+console.log(query1);
+c1.execute(query1);
+var d = c1.fetchall();
+console.log(c1.fields);
+for (let i = 0; i < d.length; i++)
+  console.log(d[i][0].valueOf());
+setTimeout(function () {
+  conn.close();
+}, 2000);
--- a/tests/gotest/batchtest.sh
+++ b/tests/gotest/batchtest.sh
@@ -17,5 +17,5 @@ go env -w GO111MODULE=on
 go env -w GOPROXY=https://goproxy.io,direct
 bash ./case001/case001.sh $severIp $serverPort
-#bash ./case002/case002.sh $severIp $serverPort
+bash ./case002/case002.sh $severIp $serverPort
 #bash ./case003/case003.sh $severIp $serverPort
--- a/tests/gotest/case001/case001.go
+++ b/tests/gotest/case001/case001.go
@@ -19,7 +19,7 @@ import (
 	"database/sql"
 	"flag"
 	"fmt"
-	_ "github.com/taosdata/driver-go/taosSql"
+	_ "github.com/taosdata/driver-go/v2/taosSql"
 	"log"
 	"strconv"
 	"time"
@@ -63,6 +63,7 @@ func main() {
 	url = "root:taosdata@/tcp(" + configPara.hostName + ":" + strconv.Itoa(configPara.serverPort) + ")/"
 	// open connect to taos server
+	fmt.Printf("url:%s",url)
 	db, err := sql.Open(taosDriverName, url)
 	if err != nil {
 		log.Fatalf("Open database error: %s\n", err)
@@ -168,17 +169,18 @@ func insert_data(db *sql.DB, demot string) {
 func select_data(db *sql.DB, demot string) {
 	st := time.Now().Nanosecond()
+	fmt.Println(demot)
 	rows, err := db.Query("select * from ? ", demot) // go text mode
+	fmt.Println("end query",err)
 	checkErr(err, "select db.Query")
 	fmt.Printf("%10s%s%8s %5s %9s%s %s %8s%s %7s%s %8s%s %4s%s %5s%s\n", " ", "ts", " ", "id", " ", "name", " ", "len", " ", "flag", " ", "notes", " ", "fv", " ", " ", "dv")
 	var affectd int
 	//decoder := mahonia.NewDecoder("gbk") // 把原来ANSI格式的文本文件里的字符，用gbk进行解码。
+	fmt.Println("start next")
 	for rows.Next() {
-		var ts string
+		var ts time.Time
 		var name string
 		var id int
 		var len int8
@@ -188,6 +190,7 @@ func select_data(db *sql.DB, demot string) {
 		var dv float64
 		err = rows.Scan(&ts, &id, &name, &len, &flag, &notes, &fv, &dv)
+		fmt.Println("rows:",err)
 		checkErr(err, "select rows.Scan")
 		fmt.Printf("%s|\t", ts)

--- a/tests/gotest/case002/case002.bat
+++ b/tests/gotest/case002/case002.bat
+@echo off
+echo ==== start run cases001.go
+del go.*
+go mod init demotest
+go build
+demotest.exe -h %1 -p %2
+cd ..
--- a/tests/gotest/case002/case002.go
+++ b/tests/gotest/case002/case002.go
+package main
+import (
+	"database/sql/driver"
+	"fmt"
+	"io"
+	"os"
+	"time"
+	taos "github.com/taosdata/driver-go/v2/af"
+)
+func Subscribe_check(topic taos.Subscriber, check int) bool {
+	count := 0
+	rows, err := topic.Consume()
+	defer func() { rows.Close(); time.Sleep(time.Second) }()
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(3)
+	}
+	for {
+		values := make([]driver.Value, 2)
+		err := rows.Next(values)
+		if err == io.EOF {
+			break
+		} else if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			os.Exit(4)
+		}
+		count++
+	}
+	if count == check {
+		return false
+	} else {
+		return true
+	}
+}
+func main() {
+	ts := 1630461600000
+	db, err := taos.Open("127.0.0.1", "", "", "", 0)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+	defer db.Close()
+	db.Exec("drop if exists database test")
+	db.Exec("create if not exists database test")
+	db.Exec("use test")
+	db.Exec("drop if exists database test")
+	db.Exec("create table test (ts timestamp ,level int)")
+	for i := 0; i < 10; i++ {
+		sqlcmd := fmt.Sprintf("insert into test values(%d,%d)", ts+i, i)
+		db.Exec(sqlcmd)
+	}
+	fmt.Println("consumption 01.")
+	topic, err := db.Subscribe(false, "test", "select ts, level from test", time.Second)
+	if Subscribe_check(topic, 10) {
+		os.Exit(3)
+	}
+	fmt.Println("consumption 02: no new rows inserted")
+	if Subscribe_check(topic, 0) {
+		os.Exit(3)
+	}
+	fmt.Println("consumption 03: after one new rows inserted")
+	sqlcmd := fmt.Sprintf("insert into test values(%d,%d)", ts+10, 10)
+	db.Exec(sqlcmd)
+	if Subscribe_check(topic, 1) {
+		os.Exit(3)
+	}
+	fmt.Println("consumption 04: keep progress and continue previous subscription")
+	topic.Unsubscribe(true)
+	topic, err = db.Subscribe(false, "test", "select ts, level from test", time.Second)
+	if Subscribe_check(topic, 0) {
+		os.Exit(3)
+	}
+}
--- a/tests/gotest/case002/case002.sh
+++ b/tests/gotest/case002/case002.sh
+#!/bin/bash
+echo "==== start run cases001.go"
+set +e
+#set -x
+script_dir="$(dirname $(readlink -f $0))"
+#echo "pwd: $script_dir, para0: $0"
+#execName=$0
+#execName=`echo ${execName##*/}`
+#goName=`echo ${execName%.*}`
+###### step 3: start build
+cd $script_dir
+rm -f go.*
+go mod init demotest > /dev/null 2>&1
+go mod tidy > /dev/null 2>&1
+go build  > /dev/null 2>&1
+sleep 1s
+./demotest -h $1 -p $2
--- a/tests/pytest/client/version.py
+++ b/tests/pytest/client/version.py
--- a/tests/pytest/concurrent_inquiry.py
+++ b/tests/pytest/concurrent_inquiry.py
--- a/tests/pytest/fulltest.sh
+++ b/tests/pytest/fulltest.sh
@@ -390,7 +390,7 @@ python3 ./test.py -f alter/alterColMultiTimes.py
 python3 ./test.py -f query/queryWildcardLength.py
 python3 ./test.py -f query/queryTbnameUpperLower.py
 python3 ./test.py -f query/query.py
+python3 ./test.py -f query/queryDiffColsOr.py
 #======================p4-end===============

--- a/tests/pytest/functions/function_interp.py
+++ b/tests/pytest/functions/function_interp.py
--- a/tests/pytest/query/queryDiffColsOr.py
+++ b/tests/pytest/query/queryDiffColsOr.py
--- a/tests/pytest/util/sql.py
+++ b/tests/pytest/util/sql.py
--- a/tests/script/fullGeneralSuite.sim
+++ b/tests/script/fullGeneralSuite.sim
--- a/tests/script/general/parser/regex.sim
+++ b/tests/script/general/parser/regex.sim
--- a/tests/script/http/httpTestSqlUtc.c
+++ b/tests/script/http/httpTestSqlUtc.c
--- a/tests/script/http/httpTestSqlt.c
+++ b/tests/script/http/httpTestSqlt.c
--- a/tests/script/http/makefile
+++ b/tests/script/http/makefile