我要感谢Greg Low先生的提问：

SELECT o.name AS ObjectName, 
       SUM(reserved_page_count) * 8.0 / 1024 AS SizeinMB
FROM sys.dm_db_partition_stats AS ps
INNER JOIN sys.sysobjects AS o
ON ps.object_id = o.id
GROUP BY o.name
ORDER BY SizeinMB DESC;

下面是另一种方法：使用SQLServerManagementStudio，在对象资源管理器中，转到数据库并选择表

然后打开“对象浏览器详细信息”（按F7或转到“查看”->“对象浏览器详情”）。在对象资源管理器详细信息页面中，右键单击列标题并启用您希望在页面中看到的列。您也可以按任何列对数据进行排序。

 exec  sp_spaceused N'dbo.MyTable'

对于所有表，请使用。。（根据保罗的评论补充）

exec sp_MSForEachTable 'exec sp_spaceused [?]'

扩展到@xav答案，处理表分区以获得MB和GB大小。在SQL Server 2008/2012上测试（注释了一行，其中is_memory_optized=1）

SELECT
    a2.name AS TableName,
    a1.rows as [RowCount],
    --(a1.reserved + ISNULL(a4.reserved,0)) * 8 AS ReservedSize_KB,
    --a1.data * 8 AS DataSize_KB,
    --(CASE WHEN (a1.used + ISNULL(a4.used,0)) > a1.data THEN (a1.used + ISNULL(a4.used,0)) - a1.data ELSE 0 END) * 8 AS IndexSize_KB,
    --(CASE WHEN (a1.reserved + ISNULL(a4.reserved,0)) > a1.used THEN (a1.reserved + ISNULL(a4.reserved,0)) - a1.used ELSE 0 END) * 8 AS UnusedSize_KB,
    CAST(ROUND(((a1.reserved + ISNULL(a4.reserved,0)) * 8) / 1024.00, 2) AS NUMERIC(36, 2)) AS ReservedSize_MB,
    CAST(ROUND(a1.data * 8 / 1024.00, 2) AS NUMERIC(36, 2)) AS DataSize_MB,
    CAST(ROUND((CASE WHEN (a1.used + ISNULL(a4.used,0)) > a1.data THEN (a1.used + ISNULL(a4.used,0)) - a1.data ELSE 0 END) * 8 / 1024.00, 2) AS NUMERIC(36, 2)) AS IndexSize_MB,
    CAST(ROUND((CASE WHEN (a1.reserved + ISNULL(a4.reserved,0)) > a1.used THEN (a1.reserved + ISNULL(a4.reserved,0)) - a1.used ELSE 0 END) * 8 / 1024.00, 2) AS NUMERIC(36, 2)) AS UnusedSize_MB,
    --'| |' Separator_MB_GB,
    CAST(ROUND(((a1.reserved + ISNULL(a4.reserved,0)) * 8) / 1024.00 / 1024.00, 2) AS NUMERIC(36, 2)) AS ReservedSize_GB,
    CAST(ROUND(a1.data * 8 / 1024.00 / 1024.00, 2) AS NUMERIC(36, 2)) AS DataSize_GB,
    CAST(ROUND((CASE WHEN (a1.used + ISNULL(a4.used,0)) > a1.data THEN (a1.used + ISNULL(a4.used,0)) - a1.data ELSE 0 END) * 8 / 1024.00 / 1024.00, 2) AS NUMERIC(36, 2)) AS IndexSize_GB,
    CAST(ROUND((CASE WHEN (a1.reserved + ISNULL(a4.reserved,0)) > a1.used THEN (a1.reserved + ISNULL(a4.reserved,0)) - a1.used ELSE 0 END) * 8 / 1024.00 / 1024.00, 2) AS NUMERIC(36, 2)) AS UnusedSize_GB
FROM
    (SELECT 
        ps.object_id,
        SUM (CASE WHEN (ps.index_id < 2) THEN row_count ELSE 0 END) AS [rows],
        SUM (ps.reserved_page_count) AS reserved,
        SUM (CASE
                WHEN (ps.index_id < 2) THEN (ps.in_row_data_page_count + ps.lob_used_page_count + ps.row_overflow_used_page_count)
                ELSE (ps.lob_used_page_count + ps.row_overflow_used_page_count)
            END
            ) AS data,
        SUM (ps.used_page_count) AS used
    FROM sys.dm_db_partition_stats ps
        --===Remove the following comment for SQL Server 2014+
        --WHERE ps.object_id NOT IN (SELECT object_id FROM sys.tables WHERE is_memory_optimized = 1)
    GROUP BY ps.object_id) AS a1
LEFT OUTER JOIN 
    (SELECT 
        it.parent_id,
        SUM(ps.reserved_page_count) AS reserved,
        SUM(ps.used_page_count) AS used
     FROM sys.dm_db_partition_stats ps
     INNER JOIN sys.internal_tables it ON (it.object_id = ps.object_id)
     WHERE it.internal_type IN (202,204)
     GROUP BY it.parent_id) AS a4 ON (a4.parent_id = a1.object_id)
INNER JOIN sys.all_objects a2  ON ( a1.object_id = a2.object_id ) 
INNER JOIN sys.schemas a3 ON (a2.schema_id = a3.schema_id)
WHERE a2.type <> N'S' and a2.type <> N'IT'
--AND a2.name = 'MyTable'       --Filter for specific table
--ORDER BY a3.name, a2.name
ORDER BY ReservedSize_MB DESC

以上查询有助于查找表（包括索引）使用的空间量，但如果要比较表上的索引使用了多少空间，请使用以下查询：

SELECT
    OBJECT_NAME(i.OBJECT_ID) AS TableName,
    i.name AS IndexName,
    i.index_id AS IndexID,
    8 * SUM(a.used_pages) AS 'Indexsize(KB)'
FROM
    sys.indexes AS i
    JOIN sys.partitions AS p ON p.OBJECT_ID = i.OBJECT_ID AND p.index_id = i.index_id
    JOIN sys.allocation_units AS a ON a.container_id = p.partition_id
WHERE
    i.is_primary_key = 0 -- fix for size discrepancy
GROUP BY
    i.OBJECT_ID,
    i.index_id,
    i.name
ORDER BY
    OBJECT_NAME(i.OBJECT_ID),
    i.index_id

我们使用表分区，由于重复记录，上面提供的查询有一些问题。

对于需要此功能的人，您可以在下面找到SQL Server 2014在生成“磁盘使用情况（按表）”报告时运行的查询。我假设它也适用于以前版本的SQL Server。

它就像一个符咒。

SELECT
    a2.name AS [tablename],
    a1.rows as row_count,
    (a1.reserved + ISNULL(a4.reserved,0))* 8 AS reserved, 
    a1.data * 8 AS data,
    (CASE WHEN (a1.used + ISNULL(a4.used,0)) > a1.data THEN (a1.used + ISNULL(a4.used,0)) - a1.data ELSE 0 END) * 8 AS index_size,
    (CASE WHEN (a1.reserved + ISNULL(a4.reserved,0)) > a1.used THEN (a1.reserved + ISNULL(a4.reserved,0)) - a1.used ELSE 0 END) * 8 AS unused
FROM
    (SELECT 
        ps.object_id,
        SUM (
            CASE
                WHEN (ps.index_id < 2) THEN row_count
                ELSE 0
            END
            ) AS [rows],
        SUM (ps.reserved_page_count) AS reserved,
        SUM (
            CASE
                WHEN (ps.index_id < 2) THEN (ps.in_row_data_page_count + ps.lob_used_page_count + ps.row_overflow_used_page_count)
                ELSE (ps.lob_used_page_count + ps.row_overflow_used_page_count)
            END
            ) AS data,
        SUM (ps.used_page_count) AS used
    FROM sys.dm_db_partition_stats ps
        WHERE ps.object_id NOT IN (SELECT object_id FROM sys.tables WHERE is_memory_optimized = 1)
    GROUP BY ps.object_id) AS a1
LEFT OUTER JOIN 
    (SELECT 
        it.parent_id,
        SUM(ps.reserved_page_count) AS reserved,
        SUM(ps.used_page_count) AS used
     FROM sys.dm_db_partition_stats ps
     INNER JOIN sys.internal_tables it ON (it.object_id = ps.object_id)
     WHERE it.internal_type IN (202,204)
     GROUP BY it.parent_id) AS a4 ON (a4.parent_id = a1.object_id)
INNER JOIN sys.all_objects a2  ON ( a1.object_id = a2.object_id ) 
INNER JOIN sys.schemas a3 ON (a2.schema_id = a3.schema_id)
WHERE a2.type <> N'S' and a2.type <> N'IT'
ORDER BY a3.name, a2.name