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  1. Teiid
  2. TEIID-4175

Certain nested dependent join structure will cause fewer results than expected

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      With a query such as:

      SELECT pm1.g1.e1, pm1.g2.e2 from /*+ makeind */ pm1.g1 inner join /*+ preserve */ (/*+ makeind */ pm1.g2 inner join pm1.g3 on pm1.g2.e2 = pm1.g3.e2) on pm1.g1.e1 = pm1.g2.e1

      There will be a join structure like:

        JoinNode(1) [Dependent] 
    AccessNode(2) 
    JoinNode(3) [Dependent] [MERGE JOIN (ALREADY_SORTED/ALREADY_SORTED)]
      DependentAccessNode(4) 
      DependentAccessNode(5)

      Such that there is a dependent join as a left child of a merge join that is marked as having that child already sorted. When there is more than 1 query needed for DependentAccessNode(4), the DependentAccessNode will mistakenly mark the right child as needing to be sorted.

              rhn-engineering-shawkins Steven Hawkins
              rhn-engineering-shawkins Steven Hawkins
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                Created:
                Updated:
                Resolved: