SQL Server - Get rows and space details for all tables in database

with tempspace as (
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 NOT LIKE 'dt%'    -- 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)

select SchemaName, TableName, 
sum(RowCounts) as RowsCount, 
sum(TotalSpaceKB)/1024/1024 as TotalGB, 
sum(UsedSpaceKB)/1024/1024 as UsedGB, 
sum(UnusedSpaceKB)/1024/1024 as UnusedGB
from tempspace 
group by SchemaName, TableName
order by TotalGB desc, SchemaName, TableName