ORACLE重设表空间的大小

ORACLE重设表空间的大小

You can enlarge a tablespace by:

• Change the size of a data file:

- Automatically during tablespace creation

SQL> CREATE TABLESPACE userdata02

DATAFILE '/u01/oradata/userdata02.dbf' SIZE 5M

AUTOEXTEND ON NEXT 2M MAXSIZE 200M;

- By specifying AUTOEXTEND after tablespace creation

SQL> ALTER DATABASE

DATAFILE '/u01/oradata/userdata02.dbf'

AUTOEXTEND ON NEXT 2M;

- Manually

SQL> ALTER DATABASE

DATAFILE '/u01/oradata/userdata02.dbf' RESIZE 5M;

• Add a data file to a tablespace

SQL> ALTER TABLESPACE userdata02

ADD DATAFILE '/u01/oradata/userdata03.dbf' SIZE 5M;

- 收缩表空间

select a.file#,a.name,a.bytes/(1024*1024) CurrentMB,

ceil(HWM * a.block_size)/(1024*1024) ResizeTo,

(a.bytes - HWM * a.block_size)/(1024*1024) ReleaseMB,

'alter database datafile '''||a.name||''' resize '||

ceil(HWM * a.block_size/(1024*1024)) || 'M;' ResizeCMD

from v$datafile a,

(select file_id,max(block_id+blocks-1) HWM

from dba_extents

group by file_id) b

where a.file# = b.file_id(+) and (a.bytes - HWM *block_size)>0

order by 5

- 针对特殊某个表空间的收缩

select a.file#,a.name,a.bytes/(1024*1024) CurrentMB,

ceil(HWM * a.block_size)/(1024*1024) ResizeTo,

(a.bytes - HWM * a.block_size)/(1024*1024) ReleaseMB,

'alter database datafile '''||a.name||''' resize '||

ceil(HWM * a.block_size/(1024*1024)) || 'M;' ResizeCMD

from v$datafile a,

(select file_id,max(block_id+blocks-1) HWM

from dba_extents c where exists

(select 1 From v$tablespace d ,v$datafile e

where d.ts#=e.ts# and d.name='单独表空间名' and e.file#=c.file_id)

group by c.file_id) b

where a.file# = b.file_id(+)

and (a.bytes - HWM *block_size)>0

order by 5