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From Dan Karp <dk...@zimbra.com>
Subject Re: Queries satisfiable from indexes
Date Tue, 20 Mar 2007 23:49:16 GMT
> You can use the following to get information about page size and
> number of pages in your table/indexes:
> http://db.apache.org/derby/javadoc/engine/org/apache/derby/diag/SpaceTable.html

Well, you're absolutely right.  It's hitting all 326 pages in the index:

   CONGLOMERATE         |IS  |ALLOC|FREE|FILL|PAGE |SPACE
   NAME                 |IDX |PAGE |PAGE|PAGE|SIZE |SAVING
   =====================+====+=====+====+====+=====+======
   I_MAIL_ITEM_TAGS_DATE|1   |326  |0   |1   |16384|0

So I guess that means there's no way to speed up the query short of teaching Derby to check
only the index prefixes when possible?

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