讲解如何检查使用空间大于90%的表空间

检查使用空间大于90%的表空间示例：

select a.tablespace_name,

totalspace,

nvl(freespace, 0) freespace,

(totalspace - nvl(freespace, 0)) used,

((totalspace - nvl(freespace, 0)) / totalspace) * 100 "%USED"

from (select tablespace_name, sum(bytes) / 1048576 totalspace

from dba_data_files

group by tablespace_name) a,

(select tablespace_name, sum(Bytes) / 1048576 freespace

from dba_free_space

group by tablespace_name) b

where a.tablespace_name = b.tablespace_name(+)

and ((totalspace - nvl(freespace, 0)) / totalspace) * 100 > 90

--and nvl(freespace,0) < 1000 -- only list TSs < 1GB free

order by 5 desc;