title | summary |
---|---|
CHARACTER_SETS |
了解 INFORMATION_SCHEMA 表 `CHARACTER_SETS`。 |
CHARACTER_SETS
表提供字符集相关的信息。TiDB 目前仅支持部分字符集。
USE INFORMATION_SCHEMA;
DESC CHARACTER_SETS;
输出结果如下:
+----------------------+-------------+------+------+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------------+-------------+------+------+---------+-------+
| CHARACTER_SET_NAME | varchar(32) | YES | | NULL | |
| DEFAULT_COLLATE_NAME | varchar(32) | YES | | NULL | |
| DESCRIPTION | varchar(60) | YES | | NULL | |
| MAXLEN | bigint(3) | YES | | NULL | |
+----------------------+-------------+------+------+---------+-------+
4 rows in set (0.00 sec)
查看 CHARACTER_SETS
表的信息:
SELECT * FROM `CHARACTER_SETS`;
输出结果如下:
+--------------------+----------------------+-------------------------------------+--------+
| CHARACTER_SET_NAME | DEFAULT_COLLATE_NAME | DESCRIPTION | MAXLEN |
+--------------------+----------------------+-------------------------------------+--------+
| ascii | ascii_bin | US ASCII | 1 |
| binary | binary | binary | 1 |
| gbk | gbk_chinese_ci | Chinese Internal Code Specification | 2 |
| latin1 | latin1_bin | Latin1 | 1 |
| utf8 | utf8_bin | UTF-8 Unicode | 3 |
| utf8mb4 | utf8mb4_bin | UTF-8 Unicode | 4 |
+--------------------+----------------------+-------------------------------------+--------+
6 rows in set (0.00 sec)
CHARACTER_SETS
表中列的含义如下:
CHARACTER_SET_NAME
:字符集名称DEFAULT_COLLATE_NAME
:字符集的默认排序规则名称DESCRIPTION
:字符集的描述信息MAXLEN
:该字符集存储一个字符所需要的最大字节数