Mysql操作主键
1.查询主键
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SELECT
t.TABLE_NAME,
t.CONSTRAINT_TYPE,
c.COLUMN_NAME,
c.ORDINAL_POSITION
FROM www.2cto.com
INFORMATION_SCHEMA.TABLE_CONSTRAINTS AS t,
INFORMATION_SCHEMA.KEY_COLUMN_USAGE AS c
WHERE
t.TABLE_NAME = c.TABLE_NAME
AND t.TABLE_SCHEMA = '
数据库名字'
AND t.CONSTRAINT_TYPE = 'PRIMARY KEY'
and t.TABLE_NAME ='表名';
2.删除主键
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alter table 表名 drop primary key;
www.2cto.com
3.增加主键
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alter table 表名 add primary key(列1,列2....);
4.修改主键
先删除主键，再添加你的新主键，操作如上2和3说明。
作者 fellting