mysql - 查询帮助

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我有一个表，其中有职员编号和学生编号，其中职员编号重复次数。

staffid | studentid
___________________
5       |     4
1       |     6
5       |     3
5       |     4
1       |     1

这样，我想按顺序选择那些职员编号。

staffid 5 (3)
staffid 1 (2)

最佳答案

如果您希望计数按降序排列，则查询中必须有一个“ order by”子句。

select staffid, count (*)
from table_name
group by staffid
order by count (*) desc