+
+
+ The above show the block distribution percentage according to the number of rows in each block. In the above example, we can get below information:
+ - `_block_dist: 3483 ||||||||||||||||| 1 (20.00%)` means there is one block whose rows is between 3,483 and 3,681.
+ - `_block_dist: 3881 ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| 4 (80.00%)` means there are 4 blocks whose rows is between 3,881 and 4,096. - The number of blocks whose rows fall in other range is zero.
+
## SHOW TAGS
```sql
@@ -230,7 +364,7 @@ Shows information about all vgroups in the system or about the vgroups for a spe
## SHOW VNODES
```sql
-SHOW VNODES [dnode_name];
+SHOW VNODES {dnode_id | dnode_endpoint};
```
Shows information about all vnodes in the system or about the vnodes for a specified dnode.
diff --git a/docs/en/12-taos-sql/25-grant.md b/docs/en/12-taos-sql/25-grant.md
index f895567c621f123778c8a711a68357a889ca0098..8b4c4393523c90595c7dd5461fc2abc73fa44c93 100644
--- a/docs/en/12-taos-sql/25-grant.md
+++ b/docs/en/12-taos-sql/25-grant.md
@@ -1,7 +1,7 @@
---
-sidebar_label: Access Control
title: User and Access Control
-description: Manage user and user's permission
+sidebar_label: Access Control
+description: This document describes how to manage users and permissions in TDengine.
---
This document describes how to manage permissions in TDengine.
diff --git a/docs/en/12-taos-sql/26-udf.md b/docs/en/12-taos-sql/26-udf.md
index 977f3bcc0844ad63e4d2fe0f28d9ca8f29c5cbd6..cb64873705c471fa23288b604df5c03fcade2ba0 100644
--- a/docs/en/12-taos-sql/26-udf.md
+++ b/docs/en/12-taos-sql/26-udf.md
@@ -1,6 +1,7 @@
---
-sidebar_label: User-Defined Functions
title: User-Defined Functions (UDF)
+sidebar_label: User-Defined Functions
+description: This document describes the SQL statements related to user-defined functions (UDF) in TDengine.
---
You can create user-defined functions and import them into TDengine.
@@ -40,7 +41,7 @@ CREATE AGGREGATE FUNCTION function_name AS library_path OUTPUTTYPE output_type [
```sql
CREATE AGGREGATE FUNCTION l2norm AS "/home/taos/udf_example/libl2norm.so" OUTPUTTYPE DOUBLE bufsize 8;
```
-For more information about user-defined functions, see [User-Defined Functions](../../develop/udf).
+For more information about user-defined functions, see [User-Defined Functions](/develop/udf).
## Manage UDF
diff --git a/docs/en/12-taos-sql/27-index.md b/docs/en/12-taos-sql/27-index.md
index 7d09bc43ab06932b82019923d4a8fda48cd99c97..7586e4af76983e785b2c6b3f03870a8bcd6df4a3 100644
--- a/docs/en/12-taos-sql/27-index.md
+++ b/docs/en/12-taos-sql/27-index.md
@@ -1,6 +1,7 @@
---
-sidebar_label: Index
-title: Using Indices
+title: Indexing
+sidebar_label: Indexing
+description: This document describes the SQL statements related to indexing in TDengine.
---
TDengine supports SMA and FULLTEXT indexing.
diff --git a/docs/en/12-taos-sql/28-recovery.md b/docs/en/12-taos-sql/28-recovery.md
index e869ffc45ff7420836d91a2536d32ce6b08a0d82..b4da25ea0c3b4f2758c981ee5bd03985ef3f2754 100644
--- a/docs/en/12-taos-sql/28-recovery.md
+++ b/docs/en/12-taos-sql/28-recovery.md
@@ -1,6 +1,7 @@
---
-sidebar_label: Error Recovery
title: Error Recovery
+sidebar_label: Error Recovery
+description: This document describes the SQL statements related to error recovery in TDengine.
---
In a complex environment, connections and query tasks may encounter errors or fail to return in a reasonable time. If this occurs, you can terminate the connection or task.
diff --git a/docs/en/12-taos-sql/29-changes.md b/docs/en/12-taos-sql/29-changes.md
index 78b6d5fc05b9b03e1e8b3af268bc357dfaa401bc..341791d6755aa66fddd98561823ee0e5ac74ba3f 100644
--- a/docs/en/12-taos-sql/29-changes.md
+++ b/docs/en/12-taos-sql/29-changes.md
@@ -1,7 +1,7 @@
---
-sidebar_label: Changes in TDengine 3.0
title: Changes in TDengine 3.0
-description: "This document explains how TDengine SQL has changed in version 3.0."
+sidebar_label: Changes in TDengine 3.0
+description: This document describes how TDengine SQL has changed in version 3.0 compared with previous versions.
---
## Basic SQL Elements
@@ -54,7 +54,6 @@ The following data types can be used in the schema for standard tables.
| 27 | GRANT | Added | Grants permissions to a user.
| 28 | KILL TRANSACTION | Added | Terminates an mnode transaction.
| 29 | KILL STREAM | Deprecated | Terminated a continuous query. The continuous query feature has been replaced with the stream processing feature.
-| 30 | MERGE VGROUP | Added | Merges vgroups.
| 31 | REVOKE | Added | Revokes permissions from a user.
| 32 | SELECT | Modified | Show Example
+
+*************************** 1.row ***************************
+_block_dist: Total_Blocks=[5] Total_Size=[93.65 Kb] Average_size=[18.73 Kb] Compression_Ratio=[23.98 %]
+
+Total_Blocks : Table `d0` contains total 5 blocks
+
+Total_Size: The total size of all the data blocks in table `d0` is 93.65 KB
+
+Average_size: The average size of each block is 18.73 KB
+
+Compression_Ratio: The data compression rate is 23.98%
+
+*************************** 2.row ***************************
+_block_dist: Total_Rows=[20000] Inmem_Rows=[0] MinRows=[3616] MaxRows=[4096] Average_Rows=[4000]
+
+Total_Rows: Table `d0` contains 20,000 rows
+
+Inmem_Rows： The rows still in memory, i.e. not committed in disk, is 0, i.e. none such rows
+
+MinRows： The minimum number of rows in a block is 3,616
+
+MaxRows： The maximum number of rows in a block is 4,096B
+
+Average_Rows： The average number of rows in a block is 4,000
+
+*************************** 3.row ***************************
+_block_dist: Total_Tables=[1] Total_Files=[2]
+
+Total_Tables: The number of child tables, 1 in this example
+
+Total_Files： The number of files storing the table's data, 2 in this example
+
+*************************** 4.row ***************************
+
+_block_dist: --------------------------------------------------------------------------------
+
+*************************** 5.row ***************************
+
+_block_dist: 0100 |
+
+*************************** 6.row ***************************
+
+_block_dist: 0299 |
+
+*************************** 7.row ***************************
+
+_block_dist: 0498 |
+
+*************************** 8.row ***************************
+
+_block_dist: 0697 |
+
+*************************** 9.row ***************************
+
+_block_dist: 0896 |
+
+*************************** 10.row ***************************
+
+_block_dist: 1095 |
+
+*************************** 11.row ***************************
+
+_block_dist: 1294 |
+
+*************************** 12.row ***************************
+
+_block_dist: 1493 |
+
+*************************** 13.row ***************************
+
+_block_dist: 1692 |
+
+*************************** 14.row ***************************
+
+_block_dist: 1891 |
+
+*************************** 15.row ***************************
+
+_block_dist: 2090 |
+
+*************************** 16.row ***************************
+
+_block_dist: 2289 |
+
+*************************** 17.row ***************************
+
+_block_dist: 2488 |
+
+*************************** 18.row ***************************
+
+_block_dist: 2687 |
+
+*************************** 19.row ***************************
+
+_block_dist: 2886 |
+
+*************************** 20.row ***************************
+
+_block_dist: 3085 |
+
+*************************** 21.row ***************************
+
+_block_dist: 3284 |
+
+*************************** 22.row ***************************
+
+_block_dist: 3483 ||||||||||||||||| 1 (20.00%)
+
+*************************** 23.row ***************************
+
+_block_dist: 3682 |
+
+*************************** 24.row ***************************
+
+_block_dist: 3881 ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| 4 (80.00%)
+
+Query OK, 24 row(s) in set (0.002444s)
+
+- SELECT does not use the implicit results column. Output columns must be specified in the SELECT clause.
- DISTINCT support is enhanced. In previous versions, DISTINCT only worked on the tag column and could not be used with JOIN or GROUP BY.
- JOIN support is enhanced. The following are now supported after JOIN: a WHERE clause with OR, operations on multiple tables, and GROUP BY on multiple tables.
- Subqueries after FROM are enhanced. Levels of nesting are no longer restricted. Subqueries can be used with UNION ALL. Other syntax restrictions are eliminated.
- All scalar functions can be used after WHERE.
- GROUP BY is enhanced. You can group by any scalar expression or combination thereof.
- SESSION can be used on supertables. When PARTITION BY is not used, data in supertables is merged into a single timeline.
- STATE_WINDOW can be used on supertables. When PARTITION BY is not used, data in supertables is merged into a single timeline.
- ORDER BY is enhanced. It is no longer required to use ORDER BY and GROUP BY together. There is no longer a restriction on the number of order expressions. NULLS FIRST and NULLS LAST syntax has been added. Any expression that conforms to the ORDER BY semantics can be used.
- Added PARTITION BY syntax. PARTITION BY replaces GROUP BY tags.
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+
+
+kafka_example_perform
+ +`kafka_example_perform` 是示例程序的入口 + +```py +{{#include docs/examples/python/kafka_example_perform.py}} +``` +
+
+
+kafka_example_common
+ +`kafka_example_common` 是示例程序的公共代码 + ```py -{{#include docs/examples/python/kafka_example.py}} +{{#include docs/examples/python/kafka_example_common.py}} ``` +
+
+
+kafka_example_producer
+ +`kafka_example_producer` 是示例程序的 producer 代码，负责生成并发送测试数据到 kafka + +```py +{{#include docs/examples/python/kafka_example_producer.py}} +``` +
+
+
+### 执行步骤
+
+kafka_example_consumer
+ +`kafka_example_consumer` 是示例程序的 consumer 代码，负责从 kafka 消费数据，并写入到 TDengine + +```py +{{#include docs/examples/python/kafka_example_consumer.py}} +``` +
+
diff --git a/docs/zh/07-develop/07-tmq.mdx b/docs/zh/07-develop/07-tmq.mdx
index 1f5a089aaa2a051e238eedc0315c37cad643b33f..fb171042d973ec8201ca0ae5f016c5d5b4324e85 100644
--- a/docs/zh/07-develop/07-tmq.mdx
+++ b/docs/zh/07-develop/07-tmq.mdx
@@ -92,22 +92,21 @@ void close() throws SQLException;
执行 Python 示例程序
+ + 1. 安装并启动 kafka + + 2. python 环境准备 + - 安装 python3 + - 安装 taospy + - 安装 kafka-python + + 3. 执行示例程序 + + 程序的执行入口是 `kafka_example_perform.py`，获取程序完整的执行参数，请执行 help 命令。 + + ``` + python3 kafka_example_perform.py --help + ``` + + 以下为创建 100 个子表，每个子表 20000 条数据，kafka max poll 为 100，一个进程，每个进程一个处理线程的程序执行命令 + + ``` + python3 kafka_example_perform.py -table-count=100 -table-items=20000 -max-poll=100 -threads=1 -processes=1 + ``` + +
+
+
+ 上面是块中包含数据行数的块儿分布情况图，这里的 0100 0299 0498 … 表示的是每个块中包含的数据行数，上面的意思就是这个表的 5 个块，分布在 3483 ~3681 行的块有 1 个，占整个块的 20%，分布在 3881 ~ 4096（最大行数）的块数为 4 个，占整个块的 80%， 其它区域内分布块数为 0。
+
+
## SHOW TAGS
```sql
@@ -231,7 +308,7 @@ SHOW [db_name.]VGROUPS;
## SHOW VNODES
```sql
-SHOW VNODES [dnode_name];
+SHOW VNODES {dnode_id | dnode_endpoint};
```
显示当前系统中所有 VNODE 或某个 DNODE 的 VNODE 的信息。
diff --git a/docs/zh/12-taos-sql/29-changes.md b/docs/zh/12-taos-sql/29-changes.md
index 1ab7f4f0169932576edf9087a825367573713b03..9d67533cdea5c055c8d3ff58000fb80ac640e271 100644
--- a/docs/zh/12-taos-sql/29-changes.md
+++ b/docs/zh/12-taos-sql/29-changes.md
@@ -54,7 +54,6 @@ description: "TDengine 3.0 版本的语法变更说明"
| 27 | GRANT | 新增 | 授予用户权限。
| 28 | KILL TRANSACTION | 新增 | 终止管理节点的事务。
| 29 | KILL STREAM | 废除 | 终止连续查询。3.0版本不再支持连续查询，而是用更通用的流计算来代替。
-| 30 | MERGE VGROUP | 新增 | 合并VGROUP。
| 31 | REVOKE | 新增 | 回收用户权限。
| 32 | SELECT | 调整 | 显示示例
+
+
+*************************** 1.row ***************************
+
+_block_dist: Total_Blocks=[5] Total_Size=[93.65 Kb] Average_size=[18.73 Kb] Compression_Ratio=[23.98 %]
+
+Total_Blocks: 表 d0 占用的 block 个数为 5 个
+
+Total_Size: 表 d0 所有 block 在文件中占用的大小为 93.65 KB
+
+Average_size: 平均每个 block 在文件中占用的空间大小为 18.73 KB
+
+Compression_Ratio: 数据压缩率 23.98%
+
+
+*************************** 2.row ***************************
+
+_block_dist: Total_Rows=[20000] Inmem_Rows=[0] MinRows=[3616] MaxRows=[4096] Average_Rows=[4000]
+
+Total_Rows: 统计表 d0 的所有行数 为20000 行（该数值仅供参考，不是精确的行数。获得精确的行数需要使用 count 函数）
+
+Inmem_Rows： 存储在写缓存中的数据行数（没有落盘），0 行表示内存缓存中没有数据
+
+MinRows： BLOCK 中最小的行数，为 3616 行
+
+MaxRows： BLOCK 中最大的行数，为 4096 行
+
+Average_Rows： 每个 BLOCK 中的平均行数，此时为 4000 行
+
+
+*************************** 3.row ***************************
+
+_block_dist: Total_Tables=[1] Total_Files=[2] Total_Vgroups=[1]
+
+Total_Tables: 子表的个数，这里为 1
+
+Total_Files： 表数据被分别保存的数据文件数量，这里是 2 个文件
+
+Total_Vgroups： 表数据分布的虚拟节点（vnode）数量
+
+
+*************************** 5.row ***************************
+
+_block_dist: 0100 |
+
+*************************** 6.row ***************************
+
+_block_dist: 0299 |
+
+......
+
+*************************** 22.row ***************************
+
+_block_dist: 3483 ||||||||||||||||| 1 (20.00%)
+
+*************************** 23.row ***************************
+
+_block_dist: 3682 |
+
+*************************** 24.row ***************************
+
+_block_dist: 3881 ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| 4 (80.00%)
+
+Query OK, 24 row(s) in set (0.002444s)
+
+- SELECT关闭隐式结果列，输出列均需要由SELECT子句来指定。
- DISTINCT功能全面支持。2.x版本只支持对标签列去重，并且不可以和JOIN、GROUP BY等子句混用。
- JOIN功能增强。增加支持：JOIN后WHERE条件中有OR条件；JOIN后的多表运算；JOIN后的多表GROUP BY。
- FROM后子查询功能大幅增强。不限制子查询嵌套层数；支持子查询和UNION ALL混合使用；移除其他一些之前版本的语法限制。
- WHERE后可以使用任意的标量表达式。
- GROUP BY功能增强。支持任意标量表达式及其组合的分组。
- SESSION可以用于超级表了。没有PARTITION BY时，超级表的数据会被合并成一条时间线。
- STATE_WINDOW可以用于超级表了。没有PARTITION BY时，超级表的数据会被合并成一条时间线。
- ORDER BY功能大幅增强。不再必须和GROUP BY子句一起使用；不再有排序表达式个数的限制；增加支持NULLS FIRST/LAST语法功能；支持符合语法语义的任意表达式。
- 新增PARTITION BY语法。替代原来的GROUP BY tags。