update tableA set col1=
(select col1 from tableA,tableB where tableA.col2=tableB.col2)
where exist(select 1 from tableA,tableB where tableA.col2=tableB.col2)
(select col1 from tableA,tableB where tableA.col2=tableB.col2)
where exist(select 1 from tableA,tableB where tableA.col2=tableB.col2)
update tableA set tableA.col1=
(select tableB.col1 from tableB where tableA.col2=tableB.col2)
where exist(select 1 from tableB where tableA.col2=tableB.col2)
update tableA set col1=
(select tableA.col1 from tableA,tableB where tableA.col2=tableB.col2)
where exists(select 1 from tableA,tableB where tableA.col2=tableB.col2) 应该没有问题.
update tableA set tableA.col1=
( select max(tableB.col1) from tableB
where tableA.col2=tableB.col2
group by tableB.col1 )
where exist(select 1 from tableB where tableA.col2=tableB.col2)