zoukankan      html  css  js  c++  java
  • sql删除相同数据(无主键)

    delete from TD21_CUST a where (a.cust_no,a.cust_name) in (select cust_no,cust_name from TD21_CUST group by cust_no,cust_name having count(*) > 1) and rowid not in
    (select min(rowid) from TD21_CUST group by cust_no,cust_name having count(*)>1)

    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 * from people where peopleId in (select peopleId from people group by peopleId 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 delete from people where   peopleName in (select peopleName    from people group by peopleName      having count(peopleName) > 1) and   peopleId not in (select min(peopleId) from people group by peopleName     having count(peopleName)>1)

    3、查找表中多余的重复记录(多个字段) select * from vitae a where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)

    4、删除表中多余的重复记录(多个字段),只留有rowid最小的记录 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、查找表中多余的重复记录(多个字段),不包含rowid最小的记录 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)  

    6.消除一个字段的左边的第一位:

    update tableName set [Title]=Right([Title],(len([Title])-1)) where Title like '村%'

    7.消除一个字段的右边的第一位:

    update tableName set [Title]=left([Title],(len([Title])-1)) where Title like '%村'

    8.假删除表中多余的重复记录(多个字段),不包含rowid最小的记录 update vitae set ispass=-1 where peopleId in (select peopleId from vitae group by peopleId,seq having count(*) > 1) and seq in (select 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) 

  • 相关阅读:
    读javascript高级程序设计08-引用类型之Global、Math、String
    读javascript高级程序设计07-引用类型、Object、Array
    读javascript高级程序设计06-面向对象之继承
    读javascript高级程序设计05-面向对象之创建对象
    读javascript高级程序设计04-canvas
    读javascript高级程序设计03-函数表达式、闭包、私有变量
    读javascript高级程序设计02-变量作用域
    C#将Word转换成PDF方法总结(基于Office和WPS两种方案)
    【转】 C#中Finally的一个不太常见的用法
    一看就懂的ReactJs入门教程-精华版
  • 原文地址:https://www.cnblogs.com/mayhh/p/11417364.html
Copyright © 2011-2022 走看看