update T2 set T2.B2=T1.B1from (Select max(A1) as A1,C1,D1from T1 group by C1,D1)T3 left joinT1 On T3.A1=T1.A1 left join T2 on t1.D1=t2.A2wheret1.C1=2000我的想法就是 把T1一样的合成一条 找到最大的A1 。然后用找到的A1去从新查一下T1表 。这样就不会有两条一样的数据。...
update cset B2=b.B1from(
select A1=max(A1),D1 from t1 group by D1) ainner join t1 b on a.A1=b.A1 and a.D1=b.D1left join t2 c on a.D1=c.A2where b.C1=2000 应该行的...
