mysql关联更新update
程序员文章站
2022-06-01 17:19:52
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https://blog.csdn.net/babyfish13/article/details/78082844
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样式1:
update xcs_user_credit_score a1,xcs_user_credit_score a2
set a1.user_currday_score=a1.user_currday_increment_score+a2.user_currday_score
where a1.pt_day='2017-09-20' and a2.pt_day='2017-09-19'
and a1.uid=a2.uid;
样式2:
update xcs_user_credit_score a1
inner join xcs_user_credit_score a2
on a1.uid=a2.uid
set a1.user_currday_score=a1.user_currday_increment_score+a2.user_currday_score
where a1.pt_day='2017-09-20' and a2.pt_day='2017-09-19'
;
突然发现mysql的一些sql语法也很神奇,像这样式的sql语句,在oracle中是行不通的,需要其他的形式。
另外的几个例子:
--sub:
update xcs_user_credit_score a1,xcs_user_credit_score a2
set a1.user_currday_score=(case when a2.user_currday_score-10>0 then a2.user_currday_score-10 else 0 end)
where a1.pt_day='2017-09-20' and a2.pt_day='2017-09-19'
and a1.uid=a2.uid
and (a1.seqing_score=0 and a1.user_silent_score=0 and a1.jubao_score=0 and a1.chengpaopao_score=0 and a1.weifan_score=0 and a1.upper_manage_score=0 and a1.pay_active_score=0 and a1.view_active_score=0 and a1.message_active_score=0 and a1.gift_active_score=0 and a1.live_active_score=0)
and a2.user_currday_score>0
;
--plus:
update xcs_user_credit_score a1,xcs_user_credit_score a2
set a1.user_currday_score=(case when a1.user_currday_score+10<0 then a1.user_currday_score+10 else 0 end)
where a1.pt_day='2017-09-20' and a2.pt_day='2017-09-19'
and a1.uid=a2.uid
and (a1.seqing_score=0 and a1.user_silent_score=0 and a1.jubao_score=0 and a1.chengpaopao_score=0 and a1.weifan_score=0)
and a1.user_currday_score<0
;