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±íA
×Ö¶ÎÃû id flag pid
1 1 111
2 3 222
3 1 111
4 1 333
5 2 222

±íB
×Ö¶ÎÃû id opention pid
1 1 111
2 1 111
3 2 111
4 1 222
5 2 222
±íC
id name
111 A
222 B
333 C
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pid flag1 flag2 opantion1
111 2 0 2
222 0 1 1
333 1 0 0

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    ) t1on c.pid=t1.pidleft?-

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    ) t1on c.pid=t1.pidleft?-

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SQL codeselect c.pid,t1.flag1,t1.flag2,t2.opantion1from cleftjoin (select pid,sum(if(flag=1,1,0))as flag1 ,sum(if(flag=2,1,0))as flag2from awhere flag=1or flag