SELECT
s.Name AS SchemaName,
t.NAME AS TableName,
p.rows AS RowCounts,
(SUM(a.total_pages) * 8) AS TotalSpaceKB,
(SUM(a.used_pages) * 8) AS UsedSpaceKB,
((SUM(a.total_pages) – SUM(a.used_pages)) * 8) AS UnusedSpaceKB
FROM
sys.tables t
INNER JOIN
sys.schemas s ON s.schema_id = t.schema_id
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 LIKE ‘if%’    — filter out system tables for diagramming
AND t.is_ms_shipped = 0
AND i.OBJECT_ID > 255
GROUP BY
t.Name, s.Name, p.Rows
ORDER BY
totalspacekb, s.Name, t.Name

SELECT
(SUM(a.total_pages) * 8) AS TotalSpaceKB
FROM
sys.tables t
INNER JOIN
sys.schemas s ON s.schema_id = t.schema_id
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 LIKE ‘if%’    — filter out system tables for diagramming
AND t.is_ms_shipped = 0
AND i.OBJECT_ID > 255
GROUP BY
t.Name, s.Name, p.Rows