临时表空间空间不足解决方法

--临时表空间空间不足解决方法

--关闭自动增长

SYS@PROD2> select * from v$version;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - Production
PL/SQL Release 11.2.0.3.0 - Production
CORE 11.2.0.3.0 Production
TNS for Linux: Version 11.2.0.3.0 - Production
NLSRTL Version 11.2.0.3.0 - Production

SYS@PROD2> alter database tempfile '/u01/app/oracle/oradata/PROD2/temp02.dbf' autoextend off;

Database altered.

SYS@PROD2> alter database tempfile '/u01/app/oracle/oradata/PROD2/temp02.dbf' resize 2m;

Database altered.

SCOTT@PROD2> select * from temp1 order by 1,2,3,4,5,6,7,8,9;
select * from temp1 order by 1,2,3,4,5,6,7,8,9
*
ERROR at line 1:
ORA-01652: unable to extend temp segment by 128 in tablespace TEMP

SCOTT@PROD2> set autot trace exp
SCOTT@PROD2> select * from temp1 order by 1,2,3,4,5,6,7,8,9;

Execution Plan
----------------------------------------------------------
Plan hash value: 3339515882

------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes |TempSpc| Cost (%CPU)| Time |
------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 10M| 1542M| | 361K (1)| 01:12:18 |
| 1 | SORT ORDER BY | | 10M| 1542M| 1904M| 361K (1)| 01:12:18 |
| 2 | TABLE ACCESS FULL| TEMP1 | 10M| 1542M| | 4909 (6)| 00:00:59 |
------------------------------------------------------------------------------------

Note
-----
- dynamic sampling used for this statement (level=2)

查看执行计划，发现估算需要1904M空间

SYS@PROD2> alter database tempfile '/u01/app/oracle/oradata/PROD2/temp02.dbf' resize 2000m;

Database altered.

SCOTT@PROD2> select * from temp1 order by 1,2,3,4,5,6,7,8,9;
54247 rows selected. --时间太长中止了

但是通过resize很难准确调整，很容易导致过度使用的问题。

11g以前只能重建表空间替换原来临时表空间。

在11g中可以使用在线回收临时表空间的功能。

SYS@PROD2> ho ls -lh /u01/app/oracle/oradata/PROD2/temp02.dbf --当前大小2G
-rw-r----- 1 oracle oinstall 2.0G Dec 13 16:55 /u01/app/oracle/oradata/PROD2/temp02.dbf

SYS@PROD2> alter tablespace temp shrink space; --使用在线回收

Tablespace altered.

SYS@PROD2> ho ls -lh /u01/app/oracle/oradata/PROD2/temp02.dbf --大小缩小为139M
-rw-r----- 1 oracle oinstall 139M Dec 13 17:01 /u01/app/oracle/oradata/PROD2/temp02.dbf

SYS@PROD2> alter tablespace temp shrink space keep 20m; --通过KEEP语句指定回收大小

Tablespace altered.

SYS@PROD2> ho ls -lh /u01/app/oracle/oradata/PROD2/temp02.dbf
-rw-r----- 1 oracle oinstall 139M Dec 13 17:01 /u01/app/oracle/oradata/PROD2/temp02.dbf
发现大小并未回收，说明这部分空间正在被使用。