MySQL中如何增加字段SQL语句

MySQL增加字段SQL语句

使用ALTER TABLE向MySQL数据库的表中添加字段

-- 向buildBaseInfo中添加字段

ALTER TABLE table_name ADD COLUMN column_name VARCHAR(100) DEFAULT NULL COMMENT '新加字段' AFTER old_column;

语句内容：

• table_name：表明；
• column_name：需要添加的字段名；
• VARCHAR(100)：字段类型为varchar，长度100；
• DEFAULT NULL：默认值NULL；
• AFTER old_column：新增字段添加在old_column字段后面。

MYSQL为多表批量新增字段

navicat中新建procedure

CREATE DEFINER=`portal`@`%` PROCEDURE `pro_AddColumn`(

	IN tab VARCHAR(100)

)

BEGIN

IF NOT EXISTS(SELECT 1 FROM information_schema.columns WHERE table_name=tab AND COLUMN_NAME='CREATE_DATE') THEN

SET @exe = CONCAT('ALTER TABLE ',tab," ADD CREATE_DATE DATE COMMENT '创建时间'");

PREPARE sql1 FROM @exe;

EXECUTE sql1;

END IF;

IF NOT EXISTS(SELECT 1 FROM information_schema.columns WHERE table_name=tab AND COLUMN_NAME='CREATE_USER') THEN

SET @exe = CONCAT('ALTER TABLE ',tab," ADD CREATE_USER VARCHAR(50) COMMENT '创建人'");

PREPARE sql1 FROM @exe;

EXECUTE sql1;

END IF;

IF NOT EXISTS(SELECT 1 FROM information_schema.columns WHERE table_name=tab AND COLUMN_NAME='MODIFIED_DATE') THEN

SET @exe = CONCAT('ALTER TABLE ',tab," ADD MODIFIED_DATE DATE COMMENT '修改时间'");

PREPARE sql1 FROM @exe;

EXECUTE sql1;

END IF;

IF NOT EXISTS(SELECT 1 FROM information_schema.columns WHERE table_name=tab AND COLUMN_NAME='MODIFIED_USER') THEN

SET @exe = CONCAT('ALTER TABLE ',tab," ADD MODIFIED_USER VARCHAR(50) COMMENT '修改人'");

PREPARE sql1 FROM @exe;

EXECUTE sql1;

END IF;

IF NOT EXISTS(SELECT 1 FROM information_schema.columns WHERE table_name=tab AND COLUMN_NAME='IP') THEN

SET @exe = CONCAT('ALTER TABLE ',tab," ADD IP VARCHAR(40) COMMENT 'ip'");

PREPARE sql1 FROM @exe;

EXECUTE sql1;

END IF;

END

把代码复制进去，保存

新建查询

CALL pro_AddColumn("tableA");

CALL pro_AddColumn("tableB");

CALL pro_AddColumn("tableC");

CALL pro_AddColumn("tableD");

代码复制进去执行即可，括号里面是表名

总结