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MySQL中如何增加字段SQL语句_Mysql

作者:胜金   更新时间: 2023-05-10 mysql

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

原文链接:https://www.cnblogs.com/JohanChan/p/13813856.html

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