查詢及刪除重復記錄的SQL語句 1、查找表中多余的重復記錄，重復記錄是根據單個字段（peopleId）來判斷 select * from people where peopleId in (select peopleId from people group by peopleId having count(peopleId) > 1)
2、刪除表中多余的重復記錄，重復記錄是根據單個字段（peopleId）來判斷，只留有rowid最小的記錄 delete from people where peopleId in (select peopleId from people group by peopleId having count(peopleId) > 1) and rowid not in (select min(rowid) from people group by peopleId having count(peopleId )>1) 注:rowid為oracle自帶不用該..... 3、查找表中多余的重復記錄（多個字段） select * from vitae a where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)
4、刪除表中多余的重復記錄（多個字段），只留有rowid最小的記錄 delete from vitae a where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1) and rowid not in (select min(rowid) from vitae group by peopleId,seq having count(*)>1) 5、查找表中多余的重復記錄（多個字段），不包含rowid最小的記錄 select * from vitae a where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1) and rowid not in (select min(rowid) from vitae group by peopleId,seq having count(*)>1) (二) 比方說 在A表中存在一個字段“name”， 而且不同記錄之間的“name”值有可能會相同， 現在就是需要查詢出在該表中的各記錄之間，“name”值存在重復的項； Select Name,Count(*) from A Group By Name Having Count(*) > 1 如果還查性別也相同大則如下: Select Name,sex,Count(*) from A Group By Name,sex Having Count(*) > 1 (三) 方法一 declare @max integer,@id integer declare cur_rows cursor local for select 主字段,count(*) from 表名 group by 主字段 having count(*) >； 1 open cur_rows fetch cur_rows into @id,@max while @@fetch ......
