SQL Server: Query all tables' size in database

drop table #tblResults

CREATE TABLE #tblResults
(
[name] nvarchar(100),
[rows] int,
[reserved] varchar(50),
[reserved_int] int default(0),
[data] varchar(100),
[data_int] int default(0),
[index_size] varchar(50),
[index_size_int] int default(0),
[unused] varchar(50),
[unused_int] int default(0)
)


-- Populate the temp table...
EXEC sp_MSforeachtable @command1= -- dark SP!
"INSERT INTO #tblResults
([name],[rows],[reserved],[data],[index_size],[unused])
EXEC sp_spaceused '?'"

-- Strip out the " KB" portion from the fields
UPDATE #tblResults SET
[reserved_int] = CAST(SUBSTRING([reserved], 1,
CHARINDEX(' ', [reserved])) AS int),
[data_int] = CAST(SUBSTRING([data], 1,
CHARINDEX(' ', [data])) AS int),
[index_size_int] = CAST(SUBSTRING([index_size], 1,
CHARINDEX(' ', [index_size])) AS int),
[unused_int] = CAST(SUBSTRING([unused], 1,
CHARINDEX(' ', [unused])) AS int)

-- Return the results...
SELECT * FROM #tblResults order by data_int desc
Drop table #tblResults