欢迎进入Oracle社区论坛,与200万技术人员互动交流 >>进入 正常来说,在完成Select语句、create index等一些使用TEMP表空间的排序操作后,Oracle是会自动释放掉临时段a的。但有些有侯我们则会遇到临时段没有被释放,TEMP表空间几乎满的状况,甚至是我们重启
欢迎进入Oracle社区论坛,与200万技术人员互动交流 >>进入
正常来说,在完成Select语句、create index等一些使用TEMP表空间的排序操作后,Oracle是会自动释放掉临时段a的。但有些有侯我们则会遇到临时段没有被释放,TEMP表空间几乎满的状况,甚至是我们重启了数据库仍没有解决问题。这个问题在论坛中也常被网友问到,下面我总结一下,给出几种处理方法。
法一、重启库
库重启时,Smon进程会完成临时段释放,TEMP表空间的清理操作,不过很多的时侯我们的库是不允许down的,所以这种方法缺少了一点的应用机会,不过这种方法还是很好用的。
法二、Metalink给出的一个方法
修改一下TEMP表空间的storage参数,让Smon进程观注一下临时段,从而达到清理和TEMP表空间的目的。
SQL>alter tablespace temp increase 1;
SQL>alter tablespace temp increase 0;
法三、我常用的一个方法,具体内容如下:
1、 使用如下语句a查看一下认谁在用临时段
SELECT username,
sid,
serial#,
sql_address,
machine,
program,
tablespace,
segtype,
contents
FROM v$session se,
v$sort_usage su
WHERE se.saddr=su.session_addr
2、 那些正在使用临时段的进程
SQL>Alter system kill session 'sid,serial#';
3、把TEMP表空间回缩一下
SQL>Alter tablespace TEMP coalesce;
法四、使用诊断事件的一种方法,也是被我认为是“杀手锏”的一种方法
1、 确定TEMP表空间的ts#
SQL>select ts#, name from sys.ts$ ;
TS# NAME
-----------------------
0 SYSYEM
1 RBS
2 USERS
3* TEMP
4 TOOLS
5 INDX
6 DRSYS
2、 执行清理操作
SQL>alter session set events 'immediate trace name DROP_SEGMENTS level 4' ;
说明:
temp表空间的TS# 为 3*, So TS#+ 1= 4
其它:
1、 出现如上问题的原因我认为可能是由于大的排序超出了TEMP表空间的空间允许范围引起的。也可能包含着其它的异常的因素。
2、 观注TEMP等这些空间的状态是Dba日常职责之一,我们可以通过Toad、Object Browser等这些工具办到,也可以用如下的语句:
SELECT UPPER(F.TABLESPACE_NAME) "表空间名",
D.TOT_GROOTTE_MB "表空间大小(M)",
D.TOT_GROOTTE_MB - F.TOTAL_BYTES "已使用空间(M)",
TO_CHAR(ROUND((D.TOT_GROOTTE_MB - F.TOTAL_BYTES) / D.TOT_GROOTTE_MB * 100,
2),
'990.99') "使用比",
F.TOTAL_BYTES "空闲空间(M)",
F.MAX_BYTES "最大块(M)"
FROM (SELECT TABLESPACE_NAME,
ROUND(SUM(BYTES) / (1024 * 1024), 2) TOTAL_BYTES,
ROUND(MAX(BYTES) / (1024 * 1024), 2) MAX_BYTES
FROM SYS.DBA_FREE_SPACE
GROUP BY TABLESPACE_NAME) F,
(SELECT DD.TABLESPACE_NAME,
ROUND(SUM(DD.BYTES) / (1024 * 1024), 2) TOT_GROOTTE_MB
FROM SYS.DBA_DATA_FILES DD
GROUP BY DD.TABLESPACE_NAME) D
WHERE D.TABLESPACE_NAME = F.TABLESPACE_NAME
ORDER BY 4 DESC

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