SELECT DISTINCT文件组和多个安装点之间的总可用空间（SQL Server）

Question

I am trying to write a query which is able to calculate the possible free space for database filegroups. I have a @table which contains the following info (this is filtered for 1 db only):

The column 'free_space' is calculated one to show the total free space in a file having in mind if the file has autogrow and the size of the mountpoint where its located.

From this table I am trying to do a select which will return me a result for all databases and their filegroups calculating the free space for them across different mount points.

Example: if 1 database has all its files on one disk - to return the free space for this disk; If it has its files on more than one disk - to return the free space for the two (or more) disks; (the free space for each file is in the table above).

So far I am here:

SELECT
database_name
,groupid
,groupname
,SUM(file_size) as file_size
 --- The next two do the same thing;
,SUM(free_space) / (count (*) * 1.0) as free_space
,AVG(free_space)
,mount_point
FROM @file_size
--where database_name = 'kosevk'
GROUP BY mount_point, database_name, groupname
ORDER BY database_name

This runs okay until I add one more file on a different disk (example is file kosevk_data7 on disk G:) - then it returns two rows for PRIMARY filegroup.

I need to have each filegroup listed only once.

Answer 1

You may remove mount_point from the GROUP BY clause and comment out mount_point in the select as below.

Hopefully it will help you.

SELECT database_name ,groupid ,groupname ,SUM(file_size) as file_size --- The next two do the same thing; ,SUM(free_space) / (count (*) * 1.0) as free_space ,AVG(free_space) --,mount_point FROM @file_size --where database_name = 'kosevk' GROUP BY database_name, groupname ORDER BY database_name

Answer 2

this seems to be the query :

;With CTE AS (SELECT
database_name
,groupid
,groupname
,SUM(file_size) as file_size
 --- The next two do the same thing;
,SUM(free_space) / (count (*) * 1.0) as free_space
,AVG(free_space)
,mount_point
FROM @file_size)
select database_name, sum(file_size), sum(free_space), mount_point
group by database_name, mount_point