mysql 修改字符集

1. 查看 my.ini 配置文件的服务端默认字符集

# 服务端默认字符集
character_set_server = utf8 

2. 查看当前数据库字符集

show VARIABLES like 'character%';

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3. 修改数据库字符集

alter database auth character set utf8;

注意：修改完数据库字符集，需要重启mysql数据库

4. 修改表字符集

ALTER TABLE  表名 DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci;

5. 生成所有表修改字符集语句

SELECT TABLE_NAME,CONCAT('ALTER TABLE  ',TABLE_NAME,' DEFAULT CHARACTER SET ',a.DEFAULT_CHARACTER_SET_NAME,' COLLATE ',a.DEFAULT_COLLATION_NAME,';') executeSQL FROM information_schema.SCHEMATA a,information_schema.TABLES b
WHERE a.SCHEMA_NAME=b.TABLE_SCHEMA
AND a.DEFAULT_COLLATION_NAME!=b.TABLE_COLLATION
AND b.TABLE_SCHEMA='数据库名' 

6. 修改列字符集

ALTER TABLE  表名 CHANGE  列名  列名  VARCHAR( 100 ) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL;

7. 生成所有列修改字符集语句

select b.table_name,b.column_name,b.character_set_name,b.collation_name
,CONCAT('ALTER TABLE ',b.table_name,' CHANGE ',b.column_name ,' ',b.column_name,' ',b.DATA_TYPE,'(',b.CHARACTER_MAXIMUM_LENGTH,') ', 'CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL;') executeSQL
 from information_schema.TABLES a,information_schema.COLUMNS b where  b.character_set_name IS NOT NULL and a.TABLE_SCHEMA=b.TABLE_SCHEMA AND a.TABLE_NAME=b.TABLE_NAME
AND a.TABLE_COLLATION!=b.COLLATION_NAME
and a.TABLE_SCHEMA='linlonge'