SQL SERVER TempDB
SELECT *
FROM (
SELECT SUM(unallocated_extent_page_count) AS [free pages]
, (SUM(unallocated_extent_page_count)*1.0/128) AS [free space in MB]
FROM tempdb.sys.dm_db_file_space_usage
) AS A cross JOIN (
SELECT SUM(size)*1.0/128 AS [size in MB]
FROM tempdb.sys.database_files
) AS B
SELECT SUM(internal_object_reserved_page_count) AS [internal object pages used]
, (SUM(internal_object_reserved_page_count)*1.0/128) AS [internal object space in MB]
FROM sys.dm_db_file_space_usage;
SELECT SUM(user_object_reserved_page_count) AS [user object pages used]
, (SUM(user_object_reserved_page_count)*1.0/128) AS [user object space in MB]
FROM sys.dm_db_file_space_usage;