RE: When to rebuild the index?

No, a select cannot cause an index split, and index splits do not necessarily warrant rebuilding anyway. Check out the following paper for an excellent of discussion of when (very rarely) and why to rebuild indexes, or do a search on asktom.oracle.com:  

www.actoug.org.au/Downloads/ <http://www.actoug.org.au/Downloads/oracle_index_internals.pdf> oracle_index_internals.pdf  

You have to run ANALYZE INDEX index_name VALIDATE STRUCTURE; to populate the index_stats view - and beware that this analyze will require a lock so you may want to run it after hours.  

Regards,
Brandon    

-----Original Message-----

From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org]On Behalf Of Chirag DBA Sent: Tuesday, September 06, 2005 9:04 AM To: Chirag DBA
Cc: Oracle-L Freelists
Subject: When to rebuild the index?

Hi Guys,  

I think that even select statement will make the index split and require the rebuilding. Am I true? I think I am.  

And there is a view called index_stats with column height.  

I have read that when the value of this column is >= 4, u need to rebuild the indexes. But after analyzing the particular schema, I don see any value to get populated in this view.  

I can see last analyzed value changed in dba_indexes when I analyze the schema with DBMS_STATS. ANALYZE_SCHEMA package.  

Why this is so?  

Regards - Chirag  

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http://www.freelists.org/webpage/oracle-l Received on Tue Sep 06 2005 - 11:27:44 CDT