Script to Check Size of Each Table


SELECT 
    t.NAME AS TableName,
    s.Name AS SchemaName,
    p.rows,
    SUM(a.total_pages) * 8 AS TotalSpaceKB, 
    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
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

If you want to get the size of each table in each database on the instance, run the following script –

SET NOCOUNT ON;
USE tempdb;
IF OBJECT_ID('tempdb..#AllDBRowCounts') IS NOT NULL DROP TABLE #AllDBRowCounts
go
CREATE TABLE #AllDBRowCounts(
DB sysname,
SchemaName sysname,
TableName sysname,
RowCounts bigint,
Used_MB bigint,
UnUsed_MB bigint,
Total_MB bigint
);

INSERT INTO #AllDBRowCounts
EXEC master.sys.sp_MSforeachdb @command1 = N'USE [?];
IF "?" NOT IN ("master","model","msdb","tempdb")
BEGIN
SELECT db_name() as DB,
s.Name AS SchemaName,
t.Name AS TableName,
p.rows AS RowCounts
,CAST(ROUND((SUM(a.used_pages) / 128.00), 2) AS NUMERIC(36, 2)) AS Used_MB,
CAST(ROUND((SUM(a.total_pages) - SUM(a.used_pages)) / 128.00, 2) AS NUMERIC(36, 2)) AS Unused_MB,
CAST(ROUND((SUM(a.total_pages) / 128.00), 2) AS NUMERIC(36, 2)) AS Total_MB
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
INNER JOIN sys.schemas s ON t.schema_id = s.schema_id
GROUP BY t.Name, s.Name, p.Rows
ORDER BY s.Name, t.Name
END';
SELECT * FROM #AllDBRowCounts ORDER BY DB,Total_MB DESC
DROP TABLE #AllDBRowCounts;
GO

Below part of the code is highlight here which runs the same script in each database