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查询重复数据sql

查询重复数据,方法如下:select * from [表A] where id in (select id from [表A] group by id having count(id) >1 )

如果后面地址都是一样,那么还可以这样 select * from 表A where name in (select distinct name from 表B ) 或者用Group by 也行

假设该表id作为pk,只保留一条shopname不重复数据 delete from shop where id not in(select min(id) from shop group by shopname) 效率不是很高,但是通用性比较强

1查询 abcd相同的记录:select * from F where a=b and b=c and c=d2查询有重复数据的记录 select * from F group by a,b,c,d having count(*)>13取出数据过滤到重复的数据 select distinct a,b,c,d from f

SELECT 某一列, COUNT( 某一列 ) FROM 表 GROUP BY 某一列 HAVING COUNT( 某一列 ) 〉1 这样查询出来的结果, 就是 有重复, 而且 重复的数量.

select count(name) c,name from student where c>1 不知道sql对不对 思路应该没问题 应该会报 不是分组 的错误吧调一调 select count(name) c,max(name) from student group by name having c>1 ??自己调一调吧,应该差不多

可用group by……having来实现.可做如下测试:1、创建表插入数据:create table test(id int,name varchar(10)) insert into test values (1,'张三')insert into test values (2,'李四')insert into test values (3,'张三')insert into test values (4,'王五')

我根据要求写了以下的SQL,不知道符不符合要求,建表SQLcreate table ta(id number,name varchar2(10))insert into ta (ID,NAME)values (1,'a');insert into ta (ID,NAME)

select id, name, memo from A where id in (select id from A group by id having count(1) >= 2) 以上回答你满意么?

select distinct * from odf_odf_length a where a < b and exists (select 'a' from odf_odf_length where a.b = a and a.a = b and a.c = c) or not exists (select 'a' from odf_odf_length where a.b = a and a.a = b and a.c = c)

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