在使用order by时将select语句嵌套在from子句中

Question

In SQL Server I try to include a select statement into a from clause while using an order by statement and I get an error "Incorrect syntax near the keyword 'group'".

select name, value, count(distinct id) as results
from (select 'test' as name, 'test 2' as value, 5 as id)
group by name, value

What is the problem with my syntax and how to do what I am trying to?

the inner select statement is just a dummy example. In my case I do have a select statement with many rows where only the id is different.

Thanks!

Answer 1

You need to give the subquery an alias, eg

select name, value, count(distinct id) as results
from (select 'test' as name, 'test 2' as value, 5 as id) AS t -- Alias Here
group by name, value;

This sucessfully returns:

name    value       results
------------------------------
test    test 2      1

Answer 2

You miss the subquery alias:

select 
    name, value, count(distinct id) as results
from 
    (select 'test' as name, 'test 2' as value, 5 as id) SQ
group by 
    name, value;