一些功能sql整理

1.查询出的一列数据(行业) 转成成一条数据以逗号分开GROUP_CONCAT

2.查询id在一个逗号分开的字段内用FIND_IN_SET


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sql: select GROUP_CONCAT(name) as industruName from industry where FIND_IN_SET(id,'4,5,6') 

3.数据转变case orgType WHEN 'virtual' THEN 0  END AS orgType

4.如果一个字段为空则返回另一个字段ifnull(u2.weixin_nickname,u2.phone)

5.查询的字段中与另一个表的一个字段拼接sql： select c.isFrozen,concat((SELECT `value` FROM dictionary WHERE `key` = 'static_resource_server_name'),c.imgUrl) AS logoUrl from table

6.select * from information_schema.INNODB_LOCKS查询锁

7.show status like '%lock%'

8.show processlist ;

9.SELECT * FROM INFORMATION_SCHEMA.INNODB_LOCK_WAITS;

10.SELECT * FROM INFORMATION_SCHEMA.INNODB_TRX;