MySQL中如何增加字段SQL语句

目录

• MySQL增加字段SQL语句
• MYSQL为多表批量新增字段
• navicat中新建procedure
• 新建查询
• 总结

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

以上为个人经验，希望能给大家一个参考，也希望大家多多支持。