Size of all tables in SQL Server

gistfile1.sql

SELECT 
    t.NAME AS TableName,
    p.rows AS RowCounts,
    (SUM(a.total_pages) * 8) / 1024 AS TotalSpaceMB, 
    (SUM(a.used_pages) * 8) / 1024 AS UsedSpaceMB, 
    ((SUM(a.total_pages) - SUM(a.used_pages)) * 8) / 1024 AS UnusedSpaceKB
FROM 
    sys.tables t
INNER JOIN      
    sys.indexes i ON t.OBJECT_ID = i.object_id
INNER JOIN 
    sys.partitions p ON i.object_id = p.OBJECT_ID AND i.index_id = p.index_id
INNER JOIN 
    sys.allocation_units a ON p.partition_id = a.container_id
WHERE 
    t.NAME NOT LIKE 'dt%' 
    AND t.is_ms_shipped = 0
    AND i.OBJECT_ID > 255 
GROUP BY 
    t.Name, p.Rows
ORDER BY 
    (SUM(a.total_pages) * 8) / 1024 DESC