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  1. Derby
  2. DERBY-4327

Implement optimizer support for bushy trees.

    Details

    • Type: Improvement
    • Status: Open
    • Priority: Major
    • Resolution: Unresolved
    • Affects Version/s: None
    • Fix Version/s: None
    • Component/s: SQL
    • Urgency:
      Normal
    • Bug behavior facts:
      Performance, Seen in production

      Description

      Currently, the optimizer only considers left-deep trees. For queries involving many tables, the best plan may be bushy. In this email thread, a user notes poor performance by Derby on queries involving 5 or more tables: http://www.nabble.com/Slow-performance-on-5-or-more-joins-in-a-star-schema-tt24708686.html

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              • Assignee:
                Unassigned
                Reporter:
                rhillegas Rick Hillegas
              • Votes:
                2 Vote for this issue
                Watchers:
                4 Start watching this issue

                Dates

                • Created:
                  Updated: