资源描述:
《查询同一表内多字段同时重复记录及sql语句》由会员上传分享,免费在线阅读,更多相关内容在工程资料-天天文库。
1、比如现在有一人员表 (表名:peosons)若想将姓名、身份证号、住址这三个字段完全相同的记录查询出来select p1.* from persons p1,persons p2 where p1.id<>p2.id and p1.cardid = p2.cardid and p1.pname = p2.pname and p1.address = p2.address可以实现上述效果.几个删除重复记录的SQL语句 1.用rowid方法2.用groupby方法3.用distinct方法 1。用
2、rowid方法据据oracle带的rowid属性,进行判断,是否存在重复,语句如下:查数据: select*fromtable1awhererowid!=(select max(rowid) fromtable1bwherea.name1=b.name1anda.name2=b.name2......)删数据: delete fromtable1awhererowid!=(select max(rowid) fromtable1bwherea.name1=b.
3、name1anda.name2=b.name2......)2.groupby方法查数据: selectcount(num),max(name)fromstudent--列出重复的记录数,并列出他的name属性 groupbynum havingcount(num)>1--按num分组后找出表中num列重复,即出现次数大于一次删数据: deletefromstudent groupbynum havingcount(num)>1 这样的话就把所有重复的都删除了。3.用distinc
4、t方法-对于小的表比较有用createtabletable_newas selectdistinct* fromtable1minuxtruncatetabletable1;insertintotable1select*fromtable_new;查询及删除重复记录的方法大全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*frompeoplewherepeopleIdin(select peopleId from people group by pe
5、opleId having count(peopleId)>1)2、删除表中多余的重复记录,重复记录是根据单个字段(peopleId)来判断,只留有rowid最小的记录deletefrompeoplewherepeopleId in(select peopleId frompeople group by peopleId having count(peopleId)>1)androwidnotin(selectmin(rowid)from people groupbypeopleId havi
6、ngcount(peopleId)>1)3、查找表中多余的重复记录(多个字段)select*fromvitaeawhere(a.peopleId,a.seq)in (selectpeopleId,seqfromvitaegroupbypeopleId,seq havingcount(*)>1)4、删除表中多余的重复记录(多个字段),只留有rowid最小的记录deletefromvitaeawhere(a.peopleId,a.seq)in (selectpeopleId,seqfromvitae
7、groupbypeopleId,seqhavingcount(*)>1)androwidnotin(selectmin(rowid)fromvitaegroupbypeopleId,seqhavingcount(*)>1)5、查找表中多余的重复记录(多个字段),不包含rowid最小的记录select*fromvitaeawhere(a.peopleId,a.seq)in (selectpeopleId,seqfromvitaegroupbypeopleId,seqhavingcount(*)>1
8、)androwidnotin(selectmin(rowid)fromvitaegroupbypeopleId,seqhavingcount(*)>1)(二)比方说在A表中存在一个字段“name”,而且不同记录之间的“name”值有可能会相同,现在就是需要查询出在该表中的各记录之间,“name”值存在重复的项;SelectName,Count(*)FromAGroupByNameHavingCount(*)>1如果还查性别也相同大则如下:SelectName,sex,Count(*)FromAG