10.4.4. SHOW语句

一些SHOW语句提供额外的字符集信息。这些语句包括SHOW CHARACTER SETSHOW COLLATIONSHOW CREATE DATABASESHOW CREATE TABLESHOW COLUMNS

SHOW CHARACTER SET命令显示全部可用的字符集。它带有一个可选的LIKE子句来指示匹配哪些字符集名。例如:

mysql> SHOW CHARACTER SET LIKE 'latin%';

+---------+-----------------------------+-------------------+--------+

| Charset | Description                 | Default collation | Maxlen |

+---------+-----------------------------+-------------------+--------+

| latin1  | cp1252 West European        | latin1_swedish_ci |      1 |

| latin2  | ISO 8859-2 Central European | latin2_general_ci |      1 |

| latin5  | ISO 8859-9 Turkish          | latin5_turkish_ci |      1 |

| latin7  | ISO 8859-13 Baltic          | latin7_general_ci |      1 |

+---------+-----------------------------+-------------------+--------+

13.5.4.1节,“SHOW CHARACTER SET语法”

SHOW COLLATION语句的输出包括全部可用的字符集。它带有一个可选的LIKE子句来指示匹配哪些 校对规则名。例如:

mysql> SHOW COLLATION LIKE 'latin1%';
+-------------------+---------+----+---------+----------+---------+
| Collation         | Charset | Id | Default | Compiled | Sortlen |
+-------------------+---------+----+---------+----------+---------+
| latin1_german1_ci | latin1  |  5 |         |          |       0 |
| latin1_swedish_ci | latin1  |  8 | Yes     | Yes      |       0 |
| latin1_danish_ci  | latin1  | 15 |         |          |       0 |
| latin1_german2_ci | latin1  | 31 |         | Yes      |       2 |
| latin1_bin        | latin1  | 47 |         | Yes      |       0 |
| latin1_general_ci | latin1  | 48 |         |          |       0 |
| latin1_general_cs | latin1  | 49 |         |          |       0 |
| latin1_spanish_ci | latin1  | 94 |         |          |       0 |
+-------------------+---------+----+---------+----------+---------+

13.5.4.2节,“SHOW COLLATION语法”

SHOW CREATE DATABASE语句显示创建给定数据库的CREATE DATABASE语句。结果包括全部数据库选项。支持DEFAULT CHARACTER SETCOLLATE。全部数据库选项存储在命名为db.Opt的文本文件中,该文件能够在数据库目录中找到。

mysql> SHOW CREATE DATABASE test;
+----------+-----------------------------------------------------------------+
| Database | Create Database                                                 |
+----------+-----------------------------------------------------------------+
| test     | CREATE DATABASE `test` /*!40100 DEFAULT CHARACTER SET latin1 */ |
+----------+-----------------------------------------------------------------+

13.5.4.4节,“SHOW CREATE DATABASE语法”

SHOW CREATE TABLESHOW CREATE DATABASE相似,但是显示创建给定数据库的CREATE TABLE语句。列定义显示任何字符集规格,并且表选项包括字符集信息。

13.5.4.5节,“SHOW CREATE TABLE语法”

当以SHOW FULL COLUMNS调用时,SHOW COLUMNS语句显示表中列的校对规则。具有CHARVARCHARTEXT数据类型的列有非NULL的 校对规则。数值列和其它非字符类型的列有NULL校对规则。例如:

mysql> SHOW FULL COLUMNS FROM person\G

*************************** 1. row ***************************

     Field: id

      Type: smallint(5) unsigned

 Collation: NULL

      Null: NO

       Key: PRI

   Default: NULL

     Extra: auto_increment

Privileges: select,insert,update,references

   Comment:

*************************** 2. row ***************************

     Field: name

      Type: char(60)

 Collation: latin1_swedish_ci

      Null: NO

       Key:

   Default:

     Extra:

Privileges: select,insert,update,references

   Comment:

字符集不是显示的部分。(字符集名隐含在校对规则名中。)

13.5.4.3节,“SHOW COLUMNS语法”

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