SELECT    t.NAME AS TableName,    s.Name AS SchemaName,    p.rows,       CAST(ROUND(((SUM(a.total_pages) * 8) / 1024.00), 2) AS NUMERIC(36, 2)) AS TotalSpaceMB,
    SUM(a.used_pages) * 8 AS UsedSpaceKB,
    CAST(ROUND(((SUM(a.used_pages) * 8) / 1024.00), 2) AS NUMERIC(36, 2)) AS UsedSpaceMB,

    (SUM(a.total_pages) - SUM(a.used_pages)) * 8 AS UnusedSpaceKB,

    CAST(ROUND(((SUM(a.total_pages) - SUM(a.used_pages)) * 8) / 1024.00, 2) AS NUMERIC(36, 2)) AS UnusedSpaceMB   ,

          CAST(ROUND((CAST(ROUND(((SUM(a.used_pages) * 8) / 1024.00), 2) AS NUMERIC(36, 2)))/1024.00,2)AS NUMERIC(36, 2)) As UsedSpaceGB

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

LEFT OUTER JOIN
    sys.schemas s ON t.schema_id = s.schema_id

WHERE
    t.NAME NOT LIKE 'dt%'
    AND t.is_ms_shipped = 0
    AND i.OBJECT_ID > 255

GROUP BY
    t.Name, s.Name, p.Rows

ORDER BY 
  TotalSpaceMB DESC, t.Name