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  1. Derby
  2. DERBY-6226

enhance optmizer to use multiple probes into multiple indexes to satisfy OR queries on different columns.

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Details

    • Improvement
    • Status: Open
    • Major
    • Resolution: Unresolved
    • 10.8.3.3, 10.11.1.1
    • None
    • SQL
    • Normal
    • High Value Fix

    Description

      For queries of the type:

      select * from a where col1 = ? or col2 = ?
      and good indexes exist on col1 and col2 it would be optimal if derby could execute a plan that
      did an index scan first on the col1 index and then an index scan on col2 index.
      Currently it looks like derby will do a full index scan if col1 and col2 are in any index, or a full table
      scan otherwise.

      Attachments

        Issue Links

          is related to

          Bug - A problem which impairs or prevents the functions of the product. DERBY-6045 in list multi-probe by primary key not chosen on tables with >256 rows

          • Major - Major loss of function.
          • Closed

          Improvement - An improvement or enhancement to an existing feature or task. DERBY-886 allow system to use 2 different access paths for 2 different columns in a select list.

          • Minor - Minor loss of function, or other problem where easy workaround is present.
          • Open

          Improvement - An improvement or enhancement to an existing feature or task. DERBY-1257 Enhance Derby optimizer and execution model to support effective use of multiple indexes on one table. Derby currently can use one index on a table and there are many situations where using multiple indexes on a table could improve performance significant

          • Minor - Minor loss of function, or other problem where easy workaround is present.
          • Open

          Improvement - An improvement or enhancement to an existing feature or task. DERBY-47 Some possible improvements to IN optimization

          • Major - Major loss of function.
          • Closed

          Activity

            People

              Unassigned Unassigned
              mikem Mike Matrigali
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              Dates

                Created:
                Updated: