Re: [转载] what's the equivalent of 'minus' (oracle) in access?
Re: [转载] what's the equivalent of 'minus' (oracle) in access?# Database - 数据库
q*j
1 楼
select a.f1, a.f2 from a except select a.f1, a.f2 from a, b where a.f1=b.f1 and a.f2=b.f2
a*a
2 楼
thanks qqj yet this doesnt work either:( the one access offers is: select a.f1, a.f2 from a LEFT JOIN b on a.f1 = b.f1 where (((a.f1) IS NULL)); who can explain LEFT JOIN for me? tia.
【在 q*j 的大作中提到】 : select a.f1, a.f2 : from a : except : select a.f1, a.f2 : from a, b : where a.f1=b.f1 : and a.f2=b.f2
q*j
3 楼
i think left join here means outer join. try this: select a.f1, a.f2 from a where a.f1 not in (select a.f1 from a, b where a.f1=b.f1) and a.f2 not in (select a.f2 from a, b where a.f2=b.f2)
【在 a*****a 的大作中提到】 : thanks qqj yet this doesnt work either:( : the one access offers is: : select a.f1, a.f2 : from a LEFT JOIN b on a.f1 = b.f1 : where (((a.f1) IS NULL)); : who can explain LEFT JOIN for me? : tia.