create table #one (id int,acc nvarchar(25))
insert into #one (id , acc) values(1,'one')
insert into #one (id , acc) values(2,'two')
insert into #one (id , acc) values(3,'three')
create table #two (acct nvarchar(25),ids int)
insert into #two (acct,ids) values('one',1)
insert into #two (acct,ids) values('two',3)
insert into #two (acct,ids) values('four',4)
select ids from #two EXCEPT select id from #one
drop table #one
drop table #two
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