SQL语句查询数据库中重复记录的个数-Mysql Tutorial-php.cn

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SQL语句查询数据库中重复记录的个数

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Jun 07, 2016 pm 05:59 PM

sqlnumberDuplicate records

一个sql语句：一个表test有四个字段id,a,b,c,如果表中的记录有三个字段a,b,c都相等，则说明这条记录是相同的，求相同的记录的个数。

代码如下:
select a,b,c,count(*) from (select c.a,c.b,c.c from test c) having count(*) >= 2 group by a,b,c

或者
代码如下:
select zdbh,tdzl,zdmj,count(*) from ecaadmin.zdsx group by zdbh,tdzl,zdmj having count(*) >= 2

Statement

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