关于两个表的问题

[liangyuan198412]

有表A中一个字段DWDM(值:12 10 45 20)
有表B中一个字段DWDM(值:12 10 45 20 23 25)
DWDM是两表的主健


怎么样把B表的数据覆盖的A表中

[mengmou]

insert A
select * from B where DWDM not in (select DWDM from A)

[zheninchangjiang]

--maybe
update a set dwdm=b.dwdm from tablea a join tableb b on charindex(a.dwdm,b.dwdm)=1

[liangyuan198412]

如果是把存在于A表不在B表中数据一起删掉的话怎么做!!

[mengmou]

delete A
where DWDM not in (select DWDM from B)

[ankor]

TRUNCATE table A
insert A select * from B
也可以..`

[liangyuan198412]

不能清楚的，还有其他的呢 !

[zheninchangjiang]

你到现在还没有描述清楚两个表主键是关系?

[david_anwei]

insert A
select * from B where DWDM not in (select DWDM from A)

[saiwong]

insert into A
select * from B where DWDM not in (select DWDM from A)

[marco08]

create table A(DWDM int)
insert A select 12
union all select 10
union all select 45
union all select 20
go
create table B(DWDM int)
insert B select 12
union all select 10
union all select 45
union all select 20
union all select 23
union all select 25
go

insert A
select DWDM from B as tmp
where not exists(select 1 from A where DWDM=tmp.DWDM)

select * from A