取出一个表中某字段相同的数据
select top 339 * from Sheet where carNO in (select carNO from Sheet group by carNO having count(*)>1) order by carNO DESC
对比两表中区分的数据并提出
select * from B where checksum(*) not in (select checksum(*) from A)
select * from kehu where checksum(车牌) not in (select checksum(车牌) from member) and checksum(客户名称)
表示是A表有,B表没有的数据.