Uploaded image for project: 'Derby'
  1. Derby
  2. DERBY-6226

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

    XMLWordPrintableJSON

    Details

    • Type: Improvement
    • Status: Open
    • Priority: Major
    • Resolution: Unresolved
    • Affects Version/s: 10.8.3.3, 10.11.1.1
    • Fix Version/s: None
    • Component/s: SQL
    • Urgency:
      Normal
    • Issue & fix info:
      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

            Activity

              People

              • Assignee:
                Unassigned
                Reporter:
                mikem Mike Matrigali
              • Votes:
                2 Vote for this issue
                Watchers:
                5 Start watching this issue

                Dates

                • Created:
                  Updated: