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SQL用select语句查询重复记录

SQL用select语句查询重复记录
http://hi.baidu.com/bilbit/blog/item/5ed5de16a6f6b412962b43eb.html
用select语句,查询重复记录
假设,表名为 T1 子段为 A,B,C
select count(*) ,A,B,C from T1
   group by A,B,C having count(*) > 1
测试数据:
    A100          B100          C100     
    A101          B101          C101     
    A102          B102          C102     
    A102          B102          C100     
    A102          B102          C102     
    A102          B102          C102     
    A100          B100          C100     
运行结果:
2    A100          B100          C100     
3    A102          B102          C102     
========================================================
选择重复,消除重复和选择出序列
有例表:emp
emp_no   name    age   &nbs


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SQL用select语句查询重复记录

SQL用select语句查询重复记录
http://hi.baidu.com/bilbit/blog/item/5ed5de16a6f6b412962b43eb.html
用select语句,查询重复记录
假设,表名为 T1 子段为 A,B,C
select count(*) ,A,B,C from T1
   group by A,B,C having count(*) > 1
测试数据:
    A100    &n ......
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