create table #tb
(
pkid int identity(1,1) primary key,
title varchar(5)
)insert #tb select 'A'
insert #tb select 'B'
insert #tb select 'C'
insert #tb select 'D'
insert #tb select 'E'
goselect count(distinct(*)) from #tb --这句为什么错
select count(distinct(pkid)) from #tb --正确能帮忙解释下原因吗?万分感谢
select count(distinct(pkid)) from #tb --正确