Oracle 10g - System Statistics

Hello guys,
i've got a question foru you :-))
If i generate new system statistics (cpu load, i/o load, etc.), are the execution plans in the sga going invalid?
Some time ago i tested it with new statistics on tables/indeces and if i generate new statistics for tables/indeces, all execution plans that refer to the object (table/indeces) are going invalid.
But under 10g, what about system stats? Are all execution plans going invalid, if new system statistics are generated? The system stats are needed to decide which access path is better.. so it would be suggestive .... i believe this would cause massive parse load.
Thanks for your answers
Regards
Stefan

From the Performance Tuning Guide, Chapter 14 Managing Optimizer Statistics
Unlike table, index, or column statistics, Oracle does not invalidate already parsed SQL statements when system statistics get updated. All new SQL statements are parsed using new statistics.
http://download-east.oracle.com/docs/cd/B19306_01/server.102/b14211/stats.htm#sthref1468

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Oracle 10g System Statisctics

Hi,
I want to know if System Statistics (CPU and I/O usage) for CBO are automatically taken and loaded in Oracle 10g or I have to schedule it manually?
can anybody help me?
Thanks in advance,
Gerald.

Basic system stats are generated at instance startup in 10g. Ideally you should still do the manual gather for better system stats values based on you workloads
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What are the different situations in which Oracle will lock existing table/index statistics automatically?
As per my undrstanding to lock the statistics we must use "dbms_stats" package with lock_table_stats/lock_schema_stats procedures. I dont see any other situation where Oracle automatically locks the statistics.
Please share your experience.

I dont see any other situation where Oracle automatically locks the statistics.Oracle never locks the statistics on its own. Oracle has only given methods so that one can decide whether to collect the statistics for volatile/static tables; so that the execution plans do not change drastically.

Gather system statistics

Hi Friends,
I want to gather system statistics in my Oracle 9.2.07 (windows) environment...
created one statistics table...
execute DBMS_STATS.CREATE_STAT_TABLE ('SYS','MY_STATS');
(2) Gathering SYSTEM Statistics Script during office hours ( 8 hours) (8am to 4pm)
begin
execute dbms_stats.gather_system_stats(
gathering_mode=> 'interval',
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END;
REM
REM
REM END of Script
REM===================================================
(3) Import the Collected System Statistics
Import the statistics daily around 8AM...because..users starts entering the transactions....
variable jobno number;
begin
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COMMIT;
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========================================================
OLAP..also i will collect during night time....
gathering system statiscs will end after 4pm....so..it takes system statistics during 8 hours interval time...and i am going to import them next day 8am..
is this the correct method????.please sched some light on this...

Hi,
Oracle recommends to gather system statistics from oracle 9i onwards....this the line from Oracle 9i R2 document...
Oracle9i Database Performance Tuning Guide and Reference
Release 2 (9.2)
Gathering System Statistics
System statistics enable the optimizer to consider a system's I/O and CPU performance and utilization. For each plan candidate, the optimizer computes estimates for I/O and CPU costs. It is important to know the system characteristics to pick the most efficient plan with optimal proportion between I/O and CPU cost.
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So better performanace, as per above document, we need system statistics.
if not needed.why it is not need...can u please describe this...
Message was edited by:
bsubbu

Oracle Database Migration(Oracle 9.2.0.4 to Oracle 10g)

I want to migrate my database from Oracle 9.2.0.4 to Oracle 10g XE, is there any method to migrate the database successfully..?
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What's the Edition of your Oracle 9.2 ?
I don't think do full export/import from 9i to Oracle 10g XE is good idea. The chance you will have problem after import is very high.
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MBRC and SYSTEM STATISTICS in Oracle 10g database.

Hi All,
I am performing database upgrade from Oracle 8i Solaris to Oracle 10g HP-UX using exp/imp method.
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SQL> select * from v$version;
BANNER
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bi
PL/SQL Release 10.2.0.4.0 - Production
CORE    10.2.0.4.0      Production
TNS for HPUX: Version 10.2.0.4.0 - Production
NLSRTL Version 10.2.0.4.0 - Production
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NAME                                 TYPE                             VALUE
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SQL> select * from AUX_STATS$
SNAME                          PNAME                               PVAL1 PVAL2
SYSSTATS_INFO                  STATUS                                    COMPLETED
SYSSTATS_INFO                  DSTART                                    11-09-2009 04:59
SYSSTATS_INFO                  DSTOP                                     11-09-2009 04:59
SYSSTATS_INFO                  FLAGS                                   1
SYSSTATS_MAIN                  CPUSPEEDNW                     128.239557
SYSSTATS_MAIN                  IOSEEKTIM                              10
SYSSTATS_MAIN                  IOTFRSPEED                           4096
SYSSTATS_MAIN                  SREADTIM
SYSSTATS_MAIN                  MREADTIM
SYSSTATS_MAIN                  CPUSPEED
SYSSTATS_MAIN                  MBRC
SYSSTATS_MAIN                  MAXTHR
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-Yasser

Maybe this article written by Tom Kite helps:
http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:499197100346264909

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Regards,
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Gathering system statistics in 10g

I am confused. I read in the OracleÂ® Database Performance Tuning Guide, for 10g Release 1, that the system statistics are NOT automatically generated and must be manually generated using DBMS_STATS. However, when I query V$SESSTAT, V$STATNAME and V$OSSTAT I have records returned.
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Thanks!

You can still manually collect stats in 10g using DBMS_STATS, but 10g can also perform statistics collection on stale tables automatically, when enabled. Our other DBA was involved in setting up that item, but I think the Oracle tool involved is the Automatic Workload Repository.
http://download-west.oracle.com/docs/cd/B14117_01/server.101/b10752/autostat.htm
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Hi,
Recreate the password file for the ASM instance as follows:
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Windows:
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I have installed oracle 10g in my winxp machine. i am using enterprise manager. i am not able to shutdown the system as it asks for os username and password. i have provided my os username and password but eerror persiste. somebody pls help me to get rid

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Here I am using Java Type IV for database
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So,is there any other way to solve this problem.What is the problem really? Do you not use dns for network naming? Maybe you have to manage the hosts file on every client then.

How to Install Oracle 10g in Windows 7 Home premium 64bit operating system

Hi,
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Mayank Adhikari

The argument would be who wants to install Oracle database on Windows 7. I think most probably by the developers who wants to "Try" something prior deal with a production database, right?
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Toad 9.7.x.x
SQL Developer
SQL/Plus
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Doubt regarding automatic statistics collection in Oracle 10g

I am using Oracle 10g in Linux
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Analyze command or DBMS_STATS package ?
AWR collects statistics(snapshots) every 1 hr but does it mean it collects only session and database related statistics and not the table related statistics?

I am using Oracle 10g in Linux Version and os name and version?
AWR collects statistics(snapshots) every 1 hr butIt's performance related statistics. Read about data gathering and AWR.
Note that AWR is an extra licensable feature thru Management packs.

SYSTEM HANGS WHILE RUNNING EXP COMMAND IN ORACLE 10G

WHEN WE ARE RUNNING THE EXP (EXPORT) COMMAND IN ORACLE 10G
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Werner

Oracle 10g on Windows 2003: Can't start with any account but Local System

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What is missing, I suspect, is reading the installation docs.
http://docs.oracle.com
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Statistics Collection in Oracle 10g

In Oracle 10g gathering table and index statistics are automatic ?
or we have to physically gather statistics for table and indexes

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Oracle 10g - System Statistics

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