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From Apache Wiki <wikidi...@apache.org>
Subject [Db-derby Wiki] Update of "DerbyBug47" by JamesSynge
Date Sun, 01 Oct 2006 14:43:49 GMT
Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Db-derby Wiki" for change notification.

The following page has been changed by JamesSynge:
http://wiki.apache.org/db-derby/DerbyBug47

------------------------------------------------------------------------------
  ||Nested Temp      || 1 query, store parameters in a temp table, use nested query, then
delete parameters ||
  ||Nested Scratch   || 1 query, store parameters in a table, use nested query, then delete
parameters ||
  ||Nested Savepoint || 1 query, set savepoint, store parameters in a table, use nested query,
then rollback savepoint ||
+ 
+ Attached to this page are two optimizer traces:
+ 
+ {{{literals-10-trace.txt}}} for 10 parameters using the Literals strategy.
+ {{{markers-10-trace.txt}}} for 10 parameters using the Markers strategy.
+ 
+ The 
+ What is most interesting is how wrong the 
+ 
+ ||Strategy||cost||rowCount||
+ ||Literals||110472||7500||
+ ||Markers||14||3.4||
+ 
  
  Here are the results for different numbers of parameters (the ID Count column below), on
a table of 100,000 rows, using
  embedded Derby.

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