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From Apache Wiki <wikidi...@apache.org>
Subject [Db-derby Wiki] Update of "DerbyBug47" by JamesSynge
Date Sun, 01 Oct 2006 15:10:27 GMT
Dear Wiki user,

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

------------------------------------------------------------------------------
  ||Strategy||cost||rowCount||Total ms (avg)||
  ||Literals||110472||7500||1021||
  ||Markers||14||3.4||3075||
+ 
+ For the Markers query, it would appear that the IN list is treated as a single predicate
to be applied to each row in the selected index (i.e. for each value of the column found in
the index, each value in the IN list is compared with that column value).
+ 
+ For the case evaluated in the test program, it would be better to treat the IN list rather
like the outer table of a nested loop join (as the results below demonstrate), where each
parameter in the IN list is used to "probe" the index.
  
  Here are the timings for all of the strategies for different numbers of parameters
  (the ID Count column below), on a table of 100,000 rows, using

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