Home Database Mysql Tutorial 开发日志:mySQL创建表时添加表和列的注释,以及查看表和列的注_MySQL

开发日志:mySQL创建表时添加表和列的注释,以及查看表和列的注_MySQL

May 27, 2016 pm 02:12 PM

开发日志:mySQL创建表时添加表和列的注释,以及查看表和列的注_MySQL

1创建表时候添加默认注释

CREATE TABLE groups(   gid INT PRIMARY KEY AUTO_INCREMENT COMMENT '设置主键自增',  
gname VARCHAR(200) COMMENT '列注释',) COMMENT='表注释'
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2修改已创建了的表注释

ALTER TABLE groups COMMENT '修改表注释'ALTER TABLE groups MODIFY COLUMN gname VARCHAR(100) COMMENT '修改列注释'
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3查看表注释 ( 我喜欢用第二个 )

SHOW  CREATE TABLE communication_group
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SELECT table_name,table_comment FROM information_schema.tables  
WHERE table_schema = '所在的db' AND table_name ='表名groups'
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4查看列注释 ( 我喜欢用第一个 )

SHOW FULL COLUMNS FROM groups-- 这个可以按条件的去搜索某名字或某数据类型的列的信息:
例如SHOW FULL COLUMNS FROM tableName WHERE FIELD = 'add_time' OR TYPE LIKE '%date%' --
 查看tableName表中列名是add_time的或类型是date的列
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SELECT  column_name, column_comment FROM information_schema.columns WHERE table_schema ='db'  
AND table_name = 'groups'
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