如何在sql server 2008中的同一个表中使用count和Group By with Self join？

Question

我有一个包含st_name和id列的表格。我需要计算st_name和按st_name分组。我该怎么做？

Answer 1

select st_name, 
       count(*) as grp_cnt,
       (select count(distinct st_name) from your_table) as st_cnt
from your_table
group by st_name