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queries on collecting schema statistics (oracle 9i) [message #177360] Wed, 14 June 2006 06:06 Go to next message
orausern
Messages: 826
Registered: December 2005
Senior Member
Hi All,

I have a few questions on this,


1) In your project do you collect statistics on sys or system account? We have the practice of not collecting schema statistics on sys and system accounts... probably because there have been some reports of systems suffering from performance issues after collecting statistics on sys.



2) Recommended way to go about collecting schema statistics...in oracle 9i with monitoring option and gather stale/auto, it is possible to collect statistics only on tables that have significant changes. Do you collect statistics regularly on time based event like at daily or weekly interval or do you collect statistics based on dml activities? (i.e. By turning on the monitoring option etc) In the later case have you experienced any problems related to statistics?

With thanks,
Nirav

Re: queries on collecting schema statistics (oracle 9i) [message #177384 is a reply to message #177360] Wed, 14 June 2006 07:03 Go to previous messageGo to next message
Mahesh Rajendran
Messages: 10707
Registered: March 2002
Location: oracleDocoVille
Senior Member
Account Moderator
1).
Depends on the case.
Usually no. But in 9i, there are a certain bugs that can be fixed by running statistics on dictionary.
2).
definately not time based. Mostly DML based.
>>In the later case have you experienced any problems related to statistics?
You are generally addressing a broad area. What are you looking into?
Re: queries on collecting schema statistics (oracle 9i) [message #177397 is a reply to message #177384] Wed, 14 June 2006 07:41 Go to previous messageGo to next message
orausern
Messages: 826
Registered: December 2005
Senior Member
Thank you Mahesh.

we have been using time based stats collection and i am exploring risks in switching to dml based stats collection. So I wanted to know that whether that switch can lead to any unexpected issues..


also one more question is: in oracle 9i, is it possible to turn monitoring on at the DATABASE level? (so you dont have to execute 1000's of individual statements to turn on monitoring at each table?)



Re: queries on collecting schema statistics (oracle 9i) [message #177404 is a reply to message #177397] Wed, 14 June 2006 07:59 Go to previous messageGo to next message
Mahesh Rajendran
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Registered: March 2002
Location: oracleDocoVille
Senior Member
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Also, have a look into dynamic sampling.
>>in oracle 9i, is it possible to turn monitoring on at the DATABASE level?
Look into
DBMS_STATS.ALTER_SCHEMA_TABLE_MONITORING and DBMS_STATS.ALTER_DATABASE_TABLE_MONITORING
Re: queries on collecting schema statistics (oracle 9i) [message #177407 is a reply to message #177404] Wed, 14 June 2006 08:02 Go to previous messageGo to next message
orausern
Messages: 826
Registered: December 2005
Senior Member
Thanks a lot. this is most helpful to me.
Re: queries on collecting schema statistics (oracle 9i) [message #177450 is a reply to message #177360] Wed, 14 June 2006 13:15 Go to previous message
asmishra
Messages: 1
Registered: June 2006
Location: HYDERABAD
Junior Member
Hi,

i require performance tunning on TOAD? how to do that?
how can i tune a package that having more than one sql query.
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