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Re: Help! This group by stmt takes AGES

From: Stephan Bressler <stephan.bressler_at_pdb.sbs.de>
Date: Fri, 26 Apr 2002 09:48:34 +0200
Message-ID: <aab0o4$t1a$1@news.mch.sbs.de> 





Hi Frank,



did you analyzed space_values? I saw cases where the RBO selected a
nested-loop with 2 full-table-scans. This is usually _very_ expensive. Even
more if the inner table is a dictionary view.
CBO (used if tables are analyzed) probably will choose a hash join for this
query.



Another solution might be to create a temporary copy of dba_tables, index it
properly and use this table for your space evaluation.



Regards


Stephan
Received on Fri Apr 26 2002 - 02:48:34 CDT












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