From e92fec2db5a34082478d70b8cb554ca22034aaec Mon Sep 17 00:00:00 2001 From: Bomin Zhang Date: Wed, 27 May 2020 17:51:15 +0800 Subject: [PATCH] td-436: update limit in document --- documentation/webdocs/markdowndocs/Super Table-ch.md | 7 ++++--- documentation/webdocs/markdowndocs/Super Table.md | 6 +++--- documentation/webdocs/markdowndocs/TAOS SQL-ch.md | 6 +++--- documentation/webdocs/markdowndocs/TAOS SQL.md | 4 ++-- documentation/webdocs/markdowndocs/connector-ch.md | 2 +- 5 files changed, 13 insertions(+), 12 deletions(-) diff --git a/documentation/webdocs/markdowndocs/Super Table-ch.md b/documentation/webdocs/markdowndocs/Super Table-ch.md index 38e6f8c17f..626f695c27 100644 --- a/documentation/webdocs/markdowndocs/Super Table-ch.md +++ b/documentation/webdocs/markdowndocs/Super Table-ch.md @@ -53,10 +53,11 @@ STable从属于库,一个STable只属于一个库,但一个库可以有一 说明: - 1. TAGS列总长度不能超过512 bytes; + 1. TAGS列总长度不能超过64k bytes; 2. TAGS列的数据类型不能是timestamp; 3. TAGS列名不能与其他列名相同; 4. TAGS列名不能为预留关键字. + 5. TAGS总数的上限是128. - 显示已创建的超级表 @@ -114,7 +115,7 @@ INSERT INTO USING TAGS (, ...) VALUES ( ADD TAG ``` - 为STable增加一个新的标签,并指定新标签的类型。标签总数不能超过6个。 + 为STable增加一个新的标签,并指定新标签的类型。标签总数不能超过128个。 - 删除标签 @@ -202,7 +203,7 @@ INSERT INTO therm4 VALUES ('2018-01-01 00:00:00.000', 23); ###3:按标签聚合查询 -查询位于北京(beijing)和天津(tianjing)两个地区的温度传感器采样值的数量count(*)、平均温度avg(degree)、最高温度max(degree)、最低温度min(degree),并将结果按所处地域(location)和传感器类型(type)进行聚合。 +查询位于北京(beijing)和天津(tianjin)两个地区的温度传感器采样值的数量count(*)、平均温度avg(degree)、最高温度max(degree)、最低温度min(degree),并将结果按所处地域(location)和传感器类型(type)进行聚合。 ```mysql SELECT COUNT(*), AVG(degree), MAX(degree), MIN(degree) diff --git a/documentation/webdocs/markdowndocs/Super Table.md b/documentation/webdocs/markdowndocs/Super Table.md index efc95c5f79..6c80c2097c 100644 --- a/documentation/webdocs/markdowndocs/Super Table.md +++ b/documentation/webdocs/markdowndocs/Super Table.md @@ -22,11 +22,11 @@ New keyword "tags" is introduced, where tag_name is the tag name, and tag_type i Note: -1. The bytes of all tags together shall be less than 512 +1. The bytes of all tags together shall be less than 64k 2. Tag's data type can not be time stamp 3. Tag name shall be different from the field name 4. Tag name shall not be the same as system keywords -5. Maximum number of tags is 6 +5. Maximum number of tags is 128 For example: @@ -168,7 +168,7 @@ You can add, delete and change the tags for a STable, and you can change the tag ALTER TABLE ADD TAG ``` -It adds a new tag to the STable with a data type. The maximum number of tags is 6. +It adds a new tag to the STable with a data type. The maximum number of tags is 128. ### Drop a Tag diff --git a/documentation/webdocs/markdowndocs/TAOS SQL-ch.md b/documentation/webdocs/markdowndocs/TAOS SQL-ch.md index cd184cbc71..81fc3ffcc4 100644 --- a/documentation/webdocs/markdowndocs/TAOS SQL-ch.md +++ b/documentation/webdocs/markdowndocs/TAOS SQL-ch.md @@ -63,7 +63,7 @@ TDengine缺省的时间戳是毫秒精度,但通过修改配置参数enableMic | 3 | BIGINT | 8 | 长整型,范围 [-2^63+1, 2^63-1], -2^63用于NULL | | 4 | FLOAT | 4 | 浮点型,有效位数6-7,范围 [-3.4E38, 3.4E38] | | 5 | DOUBLE | 8 | 双精度浮点型,有效位数15-16,范围 [-1.7E308, 1.7E308] | -| 6 | BINARY | 自定义 | 用于记录字符串,最长不能超过504 bytes。binary仅支持字符串输入,字符串两端使用单引号引用,否则英文全部自动转化为小写。使用时须指定大小,如binary(20)定义了最长为20个字符的字符串,每个字符占1byte的存储空间。如果用户字符串超出20字节,将被自动截断。对于字符串内的单引号,可以用转义字符反斜线加单引号来表示, 即 **\’**。 | +| 6 | BINARY | 自定义 | 用于记录字符串,理论上,最长可以有65526字节,但由于每行数据最多64K字节,实际上限一般小于理论值。 binary仅支持字符串输入,字符串两端使用单引号引用,否则英文全部自动转化为小写。使用时须指定大小,如binary(20)定义了最长为20个字符的字符串,每个字符占1byte的存储空间。如果用户字符串超出20字节,将被自动截断。对于字符串内的单引号,可以用转义字符反斜线加单引号来表示, 即 **\’**。 | | 7 | SMALLINT | 2 | 短整型, 范围 [-32767, 32767], -32768用于NULL | | 8 | TINYINT | 1 | 单字节整型,范围 [-127, 127], -128用于NULL | | 9 | BOOL | 1 | 布尔型,{true, false} | @@ -106,7 +106,7 @@ TDengine缺省的时间戳是毫秒精度,但通过修改配置参数enableMic ```mysql CREATE TABLE [IF NOT EXISTS] tb_name (timestamp_field_name TIMESTAMP, field1_name data_type1 [, field2_name data_type2 ...]) ``` - 说明:1)表的第一个字段必须是TIMESTAMP,并且系统自动将其设为主键;2)表的每行长度不能超过4096字节;3)使用数据类型binary或nchar,需指定其最长的字节数,如binary(20),表示20字节。 + 说明:1)表的第一个字段必须是TIMESTAMP,并且系统自动将其设为主键;2)表的每行长度不能超过64K字节;3)使用数据类型binary或nchar,需指定其最长的字节数,如binary(20),表示20字节。 - **删除数据表** @@ -402,7 +402,7 @@ count(tbname) | SELECT * FROM tb1 WHERE ts >= NOW - 1h ``` -- 查询表tb1从2018-06-01 08:00:00.000 到2018-06-02 08:00:00.000时间范围,并且clo3的字符串是'nny'结尾的记录,结果按照时间戳降序 +- 查询表tb1从2018-06-01 08:00:00.000 到2018-06-02 08:00:00.000时间范围,并且col3的字符串是'nny'结尾的记录,结果按照时间戳降序 ```mysql SELECT * FROM tb1 WHERE ts > '2018-06-01 08:00:00.000' AND ts <= '2018-06-02 08:00:00.000' AND col3 LIKE '%nny' ORDER BY ts DESC diff --git a/documentation/webdocs/markdowndocs/TAOS SQL.md b/documentation/webdocs/markdowndocs/TAOS SQL.md index 99aa73b435..2b9960b860 100644 --- a/documentation/webdocs/markdowndocs/TAOS SQL.md +++ b/documentation/webdocs/markdowndocs/TAOS SQL.md @@ -39,7 +39,7 @@ The full list of data types is listed below. For string types of data, we will | 6 | DOUBLE | 8 | A standard nullable double float type with 15-16 significant digits and a range of [-1.7E308, 1.7E308]​ | | 7 | BOOL | 1 | A nullable boolean type, [**`true`**, **`false`**] | | 8 | TIMESTAMP | 8 | A nullable timestamp type with the same usage as the primary column timestamp | -| 9 | BINARY(*M*) | *M* | A nullable string type whose length is *M*, any exceeded chars will be automatically truncated. This type of string only supports ASCii encoded chars. | +| 9 | BINARY(*M*) | *M* | A nullable string type whose length is *M*, any exceeded chars will be automatically truncated, the maximum length of *M* is 65526, but as maximum row size is 64K bytes, the actual upper limit will generally less than 65526. This type of string only supports ASCii encoded chars. | | 10 | NCHAR(*M*) | 4 * *M* | A nullable string type whose length is *M*, any exceeded chars will be truncated. The **`NCHAR`** type supports Unicode encoded chars. | All the keywords in a SQL statement are case-insensitive, but strings values are case-sensitive and must be quoted by a pair of `'` or `"`. To quote a `'` or a `"` , you can use the escape character `\`. @@ -86,7 +86,7 @@ All the keywords in a SQL statement are case-insensitive, but strings values are 1) The first column must be a `timestamp`, and the system will set it as the primary key. - 2) The record size is limited to 4096 bytes + 2) The record size is limited to 64k bytes 3) For `binary` or `nchar` data types, the length must be specified. For example, binary(20) means a binary data type with 20 bytes. diff --git a/documentation/webdocs/markdowndocs/connector-ch.md b/documentation/webdocs/markdowndocs/connector-ch.md index 47c8381f69..3cd8da1bd5 100644 --- a/documentation/webdocs/markdowndocs/connector-ch.md +++ b/documentation/webdocs/markdowndocs/connector-ch.md @@ -2,7 +2,7 @@ TDengine提供了丰富的应用程序开发接口,其中包括C/C++、JAVA、Python、RESTful、Go等,便于用户快速开发应用。 -注意:所以执行 SQL 语句的 API,例如 C/C++ Connector 中的 `tao_query`、`taos_query_a`、`taos_subscribe` 等,以及其它语言中与它们对应的API,每次都只能执行一条 SQL 语句,如果实际参数中包含了多条语句,它们的行为是未定义的。 +注意:所有执行 SQL 语句的 API,例如 C/C++ Connector 中的 `tao_query`、`taos_query_a`、`taos_subscribe` 等,以及其它语言中与它们对应的API,每次都只能执行一条 SQL 语句,如果实际参数中包含了多条语句,它们的行为是未定义的。 ## C/C++ Connector -- GitLab