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标题: update问题 [打印本页]

作者: ARISYANG    时间: 2007-02-15 10:09
标题: update问题
create table a(
a varchar(10) null,
b number(5) null
)
insert into a values ('a','1')
insert into a values ('a','2')
insert into a values ('a','3')
insert into a values ('b','4')
insert into a values ('b','5')

create table b(
a varchar(10) null,
b number(5) null
)
insert into b(a) (select distinct a from b)
现在b表有数据a,b
我现在的需求是update b set b=count(*) from
(
select a,count(b)
from a
group by a
)
where a.a=b.a
请问怎么写SQL?
作者: jasonshan    时间: 2007-02-16 10:24
select a,count(b) as b into #tmp1 from a group by a
update b set b.b=#tmp1.b from #tmp1 where b.a=#tmp1.a
作者: ARISYANG    时间: 2007-02-16 16:40
恩,就是这样做的,不能用子查询

用动态的SQL可以吗?




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