1. 替换某个字段中的部分内容
SET @oldlink1 = ‘http://192.168.100.66‘; SET @newlink1 = ‘www.baidu.com‘; UPDATE Test1 SET Content = ( REPLACE ( Content ,@oldlink1 ,@newlink1 ) ) WHERE Content LIKE concat(‘%‘ ,@oldlink1, ‘%‘);
2.连表删除数据
SET @UnitId = ‘27542‘; DELETE t1 FROM Test1 AS t1 INNER JOIN Test2 AS t2 ON t1.Code = t2.Code WHERE t2.UnitId NOT IN (@UnitId);
3.连表插入数据
INSERT INTO Test ( ID, PostTime ) SELECT UUID() AS ID, t1.PostTime FROM Test1 AS t1 INNER JOIN Test2 AS t2 ON t1.Code = t2.Code;
4. 连表更新数据
UPDATE Test1 AS t1 INNER JOIN Test2 AS t2 ON t1.Code = t2.Code SET t1.NextFlowNodeId = 72 WHERE t1.ProcessStepId = 70;
5.获取某个库下的所有表名
select table_name from information_schema.tables where [email protected]
6.获取某个表的所有字段名
select COLUMN_NAME from information_schema.COLUMNS where table_name = @tableName and table_schema = @dbName;
7.CONCAT 拼接字符串
SET @SearchText= CONCAT(‘%‘,‘测试‘,‘%‘); SELECT * FROM Test3 WHERE CONCAT(ItemName,ItemNumber,DeptName,RealName) LIKE @SearchText;
注意:若拼接项中存在NULL值,结果为NULL。如 CONCAT(‘测试‘,‘001‘,NULL,‘小明‘),结果为NULL,并不是我们想要的结果:"测试001小明"
原文地址:https://www.cnblogs.com/zhuanjiao/p/12123058.html
时间: 2024-10-08 19:06:04