如何用sql语句查询和删除表中重复数据

时间 2019-11-10

标签如何 sql 语句查询删除表中重复数据栏目 SQL 繁體版

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一、查询表中重复数据（单字段） Select * From 表 Where 字段1 In (Select 字段1 From 表 Group By 字段1 Having Count(字段1) > 1) table

二、删除表中多余的重复记录，只留有rowid最小的记录（单字段） Delete From 表 Where 字段1 In (Select 字段1 From 表 Group By 字段1 Having Count(字段1) > 1) And Rowid Not In (Select Min(Rowid) From 表 Group By 字段1 Having Count(字段1) > 1) select

三、查找表中多余的重复记录（多个字段） Select * From 表 a Where (a.字段1, a.字段2) In (Select 字段1, 字段2 From 表 Group By 字段1, 字段2 Having Count(*) > 1) 数据

四、删除表中多余的重复记录，只留有rowid最小的记录（多个字段） Delete From 表 a Where (a.字段1, a.字段2) In (Select 字段1, 字段2 From 表 Group By 字段1, 字段2 Having Count(*) > 1) And Rowid Not In (Select Min(Rowid) From 表 Group By 字段1, 字段2 Having Count(*) > 1) 查询

5.删除多于的重复记录（单个字段，多个字段） delete from table where id not in ( select min(id) from table group by name) 或者 delete from table where id not in ( select min(id) from table group by 字段1，字段2) tab

6.删除多余的重复记录（单个字段，多个字段） delete from table where id in ( select max(id) from table group by name having count(*)>1) vi

七、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 * From 表 a Where (a.字段1, a.字段2) In (Select 字段1, 字段2 From 表 Group By 字段1, 字段2 Having Count(*) > 1) And Rowid Not In (Select Min(Rowid) From 表 Group By 字段1, 字段2 Having Count(*) > 1)co

八、查单个字段的重复次数 Select Name,sex,Count(*) From A Group By Name,sex Having Count(*) > 1let