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解析Oracle查詢和刪除JOB的SQL

本篇文章是對Oracle查詢和刪除JOB的SQL的實現方法進行了詳細的分析介紹,需要的朋友參考下  

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 ......

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