SQL: Tamaño de tablas

SET NOCOUNT ON
DBCC UPDATEUSAGE(0)
-- Table row counts and sizes.
DECLARE @sizes TABLE
(
    [name] NVARCHAR(128),
    [rows] CHAR(11),
    reserved VARCHAR(18),
    data VARCHAR(18),
    index_size VARCHAR(18),
    unused VARCHAR(18)
)
INSERT @sizes EXEC sp_msForEachTable 'EXEC sp_spaceused ''?'''
SELECT *
FROM   @sizes
ORDER BY convert(int, substring(data, 1, len(data)-3)) desc