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From kashyup <va...@quantum4d.com>
Subject Few quick questions on Index, Optimizer
Date Wed, 11 Nov 2009 23:49:26 GMT

Hello all, after going through much docs i think i have lost answers to much
basic questions. I would appreciate any reply...

Q1) Derby generates Index on a PK, what is the best/efficient way to rebuild
index on a PK? 

Q2) In a certain join query, on the inner query using PK index on a table w/
32k records, my Query Optimizer outputs "Number of pages visited=1083". What
should I change, derby.storage.pageSize or derby.storage.pageCacheSize to
reduce no. of pages visited?

Q3) Why is it that despite doing proper shutdown, if i start my app on derby
after a day it is very slow the first time. Any thoughts? solution?

Q4) Calling CALL SYSCS_UTIL.SYSCS_COMPRESS_TABLE(?, ?, ?) right after the
app starts on Derby, makes the same queries take much longer once the above
proc has finished executing. Any thoughts?

Thanks all!

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