跟新一对多的关系表

update duanpai as d
inner join (select duanpai_id,count(*) as num1 from duanpai_gentie GROUP BY duanpai_id) as g ON g.duanpai_id=d.id
inner join (select duanpai_id,count(*) as num2 from duanpai_huifu GROUP BY duanpai_id) as h ON h.duanpai_id=d.id

set huifu_times=num1+num2.

1,duanpai与duanpai_gentie,duanpai与duanpai_huifu表都是1对多的关系。

2,duanpai表中的huifu_times是统计duanpai_gentie,duanpai_huifu两个表中的数据。


思路:同一个表不能再查询的时候,跟新。对于一个表来说查询与跟新是不能同时的



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转载自blog.csdn.net/zdw19861127/article/details/80803250