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From Mike Matrigali <mikem_...@sbcglobal.net>
Subject Re: Optimizer hints?
Date Tue, 21 Dec 2004 00:41:58 GMT
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Currently derby does not use stats for data distribution, it uses the
existing indexes.

Dibyendu Majumdar wrote:
| Hi, I would agree with you that the third option is best.
|
|
|>   3. Provide an offline tool which registers hints for SQL statements.
|>When those SQL statements are executed, Derby could look up previously
|>registered hints for those statements and automatically apply them.
|>Advantage of this scheme is that applications don't need to be modified
|>to add hints and they can easily be removed when not needed. How exactly
|>to register the hints could be worked out. I personally prefer this
|>approach.
|
|
| How about manipulating the stats used by the optimizer and then
storing the
| execution plan in a table? This is also a technique that is available in
| Oracle.
|
| Regards
|
|
|
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