写一个db2的update语句

显示全部楼层 · 2011-6-11 09:10:43

db2中有两张表A(a,b,c)B(d,e,f)，其中B依赖于A(A.a=B.e)。写一个update语句将A表中c的值写到B表中的f字段

千问 · 2011-6-11 09:10:43

select a1.a10,a11,b2.a10,b21 from a1 inner join b2 on a1.a10=b2.a10 where a11b21update b2 inner join (select a1.a10,a11 from a1 inner join b2 on a1.a10=b2.a10 where a11b21) total on b2.a10=total.a10 set b2.b21=total.a11;前面那个是查询后面是修改只对a11和b21值不同的做修改而相同的就跳过这样效率也提高了不过我这个是mysql的语句DB2不懂应该差不多你可以试试另...

千问 · 2011-6-11 09:10:43

merge into Busing (select a.a,a.c from A) as don b.e = d.awhen matched then update set b.f = d.c;...

千问 · 2011-6-11 09:10:43

update B set B.f=(select A.c from A where A.a=B.e)...

千问 · 2011-6-11 09:10:43

update B set f=(select c from A where A.a=B.e)...