计算模式中表的大小

Question

我正在尝试在我的模式中查找表的大小。我试着通过dba_extent查找，如下所示。

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;

它显示为2MB，但不可能是2MB，当我导出schema.It时，我在日志中看到它的大小约为800MB，当我查询dba_segments时，也给出了相同的结果。谁能帮我到哪里去wrong.thanks占用你的时间。

Answer 1

尝试下面的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)