mysql如何实现行转列
程序员文章站
2022-03-24 11:35:31
...
mysql实现行转列的方法:1、用cross join的方式实现,代码为【cross join(select sum(a.kills) '猪八戒】;2、用case语句的方式实现,代码为【case when user_name='孙悟空'】。
本教程操作环境:windows7系统、mysql8.0.22版,该方法适用于所有品牌电脑。
mysql实现行转列的方法:
1、用cross join的方式实现
select * from (select sum(a.kills) '孙悟空' from kills1 as a LEFT JOIN tssrz as b on a.user_id = b.id WHERE b.user_name = '孙悟空' GROUP BY b.user_name) e cross join (select sum(a.kills) '猪八戒' from kills1 as a LEFT JOIN tssrz as b on a.user_id = b.id WHERE b.user_name = '猪八戒' GROUP BY b.user_name) f
2、用case语句的方式实现
SELECT sum(case when user_name='孙悟空' then kills end) as '孙悟空', sum(case when user_name='猪八戒' then kills END) as '猪八戒', sum(case when user_name='沙和尚' then kills END) as '沙和尚' from tssrz as a join kills1 as b on a.id = b.user_id
相关免费学习推荐:mysql视频教程
以上就是mysql如何实现行转列的详细内容,更多请关注其它相关文章!
上一篇: 用Java访问带有Kerberos认证的HBase
下一篇: php基于什么引擎