摘要：
1、查找表中多余的重复记录，重复记录是根据单个字段（peopleId）来判断 select*frompeople wherepeopleIdin(selectpeopleIdfrompeoplegroupbypeopleIdhavingcount(peopleId)>1) 例二： select * from testtable where numeber in (select number from people group by number having count(number) > 1 ) 可以查出testtable表中number相同的记录 2、删除表中多余的重复记录，重 阅读全文