mysql按照某一字段去重,并显示其他字段信息 ? 最近有一个需求按照sql中的某一列值去重,还要显示其他字段的信息, 使用select distinct name, sorce from table,结果发现去重不起作用,因为MYSQL认为要sorce和name同时重复才会去除。 ??? Google一番,反复
mysql按照某一字段去重,并显示其他字段信息?
最近有一个需求按照sql中的某一列值去重,还要显示其他字段的信息,
使用select distinct name, sorce from table,结果发现去重不起作用,因为MYSQL认为要sorce和name同时重复才会去除。
??? Google一番,反复试验最终解决办法如下:
??? select *, count(distinct name) from table group by name
??? 如果SQL语句还有limit,order by等条件,必须放在group by后面。
这样就达到了既去重,又能够输出更多字段信息的目的.
记录之,以备忘,给大家提供帮助。

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