计算模式中表的大小

Question

我正在尝试在我的架构中查找表的大小。我尝试通过 dba_extent 查找如下。

select segment_name,sum(bytes)/(1024*1024) size from  dba_extent where segment_type='TABLE'
and segment_name = 'mytablename'
and owner ='myschemaname'
group by segment_name;

它给出的大小为 2 MB，但绝不可能是 2MB，而且我在导出模式时在日志中看到它的大小约为 800MB。当我查询 dba_segments 时，它给出了相同的结果。谁能帮我解决我出错的地方。感谢您的宝贵时间。

Answer 1

试试下面的 SQL：希望这会有所帮助:)

SELECT 
tbl.NAME AS TableName,
idx.name as indexName,
prts.[Rows],
sum(a.total_pages) as TotalPages, 
sum(a.used_pages) as UsedPages, 
sum(a.data_pages) as DataPages,
(sum(a.total_pages) * 8) / 1024 as TotalSpaceMB, 
(sum(a.used_pages) * 8) / 1024 as UsedSpaceMB, 
(sum(a.data_pages) * 8) / 1024 as DataSpaceMB
FROM 
sys.tables tbl
INNER JOIN 
sys.indexes idx ON tbl.OBJECT_ID = idx.object_id
INNER JOIN 
sys.partitions prts ON idx.object_id = prts.OBJECT_ID AND idx.index_id = prts.index_id
INNER JOIN 
sys.allocation_units a ON prts.partition_id = a.container_id
WHERE 
tbl.NAME NOT LIKE 'dt%' AND
idx.OBJECT_ID > 255 AND 
idx.index_id <= 1
GROUP BY 
tbl.NAME, idx.object_id, idx.index_id, idx.name, prts.[Rows]
ORDER BY 
object_name(idx.object_id)