statistics_level参数的介绍

statistics_level参数的介绍

statistics_level控制数据库收集统计信息的级别，有三个参数值:

BASIC :收集基本的统计信息
TYPICAL：收集大部分统计信息(数据库的默认设置)
ALL：收集全部统计信息

[oracle@linuxoracle oracle]$ sqlplus "/ as sysdba"

SQL*Plus: Release 9.2.0.4.0 - Production on Fri Nov 16 09:47:38 2007

Copyright (c) 1982, 2002, Oracle Corporation. All rights reserved.

Connected to:
Oracle9i Enterprise Edition Release 9.2.0.4.0 - Production
With the Partitioning, OLAP and Oracle Data Mining options
JServer Release 9.2.0.4.0 - Production

sys@DG1> desc v$statistics_level;
Name Null? Type
----------------------------------------------------- -------- ------------------------------------
STATISTICS_NAME VARCHAR2(64)
DESCRIPTION VARCHAR2(4000)
SESSION_STATUS VARCHAR2(8)
SYSTEM_STATUS VARCHAR2(8)
ACTIVATION_LEVEL VARCHAR2(7)
STATISTICS_VIEW_NAME VARCHAR2(64)
SESSION_SETTABLE VARCHAR2(3)

sys@DG1> select STATISTICS_NAME,ACTIVATION_LEVEL,STATISTICS_VIEW_NAME from v$statistics_level;

STATISTICS_NAME ACTIVAT STATISTICS_VIEW_NAME
---------------------------------------- ------- ----------------------------------------------------------------
Buffer Cache Advice TYPICAL V$DB_CACHE_ADVICE
MTTR Advice TYPICAL V$MTTR_TARGET_ADVICE
Timed Statistics TYPICAL
Timed OS Statistics ALL
Segment Level Statistics TYPICAL V$SEGSTAT
PGA Advice TYPICAL V$PGA_TARGET_ADVICE
Plan Execution Statistics ALL V$SQL_PLAN_STATISTICS
Shared Pool Advice TYPICAL V$SHARED_POOL_ADVICE

8 rows selected.