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sql字段查重

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sql字段查重

select * from shiyan003 a where exists (select 1 from (select xm, sfzhm from shiyan003 group by xm, sfzhm having count(*) > 1) s where xm = xm and sfzhm = sfzhm)

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 )

应该是in关键字不支持多字段吧,你这样试一下select *  from shiyan003 a where exists (select 1          from (select xm, sfzhm                  from shiyan003                 group by xm, sfzhm                having count(*) > 1) s         where xm = xm           and sfzhm = sfzhm)

select * from shiyan003 awhere xm in (select xm from shiyan003 group by xm,sfzhm having count(*) > 1)and sfzhm in (select sfzhm from shiyan003 group by xm,sfzhm having count(*) > 1)原句的错在in的使用上

查重sql语句

select 姓名,地址,手机号 from a,b where 手机号=手机号

select * from table1 b where bill_id=(select top 1 bill_id from table1 a where exists(select top 1 column1 from table1 where column1=lumn1 group by column1 having count(*)>1 order by column1) and lumn1=lumn1) order by column1SQL语句查询有部份字段重复的第一条数据

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。

你的图中post_content全一样,post_title有两种,这算不算重复呀?我按post_content重复就查找出来。查重:select post_content,post_title from wp_posts group by post_content having count(post_content)>1删除要先将数据查询到临时表中,然后将原表清空,在追加回来。

sql查重函数

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 id,count(1) 重复次数 from A group by id having count(1)>1;查询出来的结果都是id重复的,重复次数 中的数值就是重复了多少次。

去重函数?什么意思?去掉重复的记录?

列出表中某字段有重复的记录,每条记录后面带重复次数。 例如: id name -------- 1 aaa 2 bbb 3 ccc 4 bbb 5 aaa 6 aaa 7 ccc 8 ddd 9 eee 查询结果应如下: id name repeat ----------------- 1 aaa 3 5 aaa 3 6 aaa 3 2 bbb 2 4 bbb 2 3 ccc 2 7 ccc 2 第一种解决方案:SELECT Aid, Aame, BpeatFROM Table_1 AS A INNER JOIN (SELECT name, COUNT(*) AS repeat FROM Table_1 GROUP BY name) AS B ON Aame = BameWHERE (Bpeat > 1)ORDER BY Aame, Aid第二种解决方案:SELECT name, COUNT(*) AS repeatFROM Table_1GROUP BY nameHAVING (COUNT(*) > 1)我觉得你应该把表和字段列出来,这样别人的回答可以更明晰化哪几个字段或者哪个字段要查重的?

sql语句查重

我的想法是比较count(列)和count(distinct 列)是否相等。不知道大家有没有更好的方法。

你的图中post_content全一样,post_title有两种,这算不算重复呀?我按post_content重复就查找出来。查重:select post_content,post_title from wp_posts group by post_content having count(post_content)>1删除要先将数据查询到临时表中,然后将原表清空,在追加回来。

使用临时表求出重复记录select userid from t_name group by userid having count(*) > 1求出不重复记录select distinct * into #a1 from t_name where userid in select userid from t_name group by userid having count(*) > 1删除重复记录从#a1取出不重复记录

SELECT *, count(*) AS CCCFROM 表明GROUP BY 字段ORDER BY CCC DESC

查重语句sql

你表里就俩字段的话不太好弄,如果有第三个字段select post_content,post_title from wp_posts group by post_content,post_title having count(*)>1先看看有多少重复的假设你表中还有id的一个字段select min(id),post_content,post_title from wp_posts group by post_content,post_title这些选出来后你看看这些是否可以不删除然后delete from wp_posts where id not in (select min(id) from wp_posts group by post_content,post_title) 没懂你补充的那句话是什么意思 那就是你上边的图里,你要把第一条和第三条删除呗?还有你问的那个字符集的问题,是瑞典,不是雅典

我的想法是比较count(列)和count(distinct 列)是否相等。不知道大家有没有更好的方法。

你的图中post_content全一样,post_title有两种,这算不算重复呀?我按post_content重复就查找出来。查重:select post_content,post_title from wp_posts group by post_content having count(post_content)>1删除要先将数据查询到临时表中,然后将原表清空,在追加回来。

selectid,name,memofromAwhereidin(selectidfromAgroupbyidhavingcount(1)>=2)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

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