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  1. Tajo
  2. TAJO-619

SELECT count(1) after joins on text keys causes wrong plans

    Details

    • Type: Bug
    • Status: Resolved
    • Priority: Minor
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 0.8.0, 0.9.0
    • Component/s: Planner/Optimizer
    • Labels:
      None

      Description

      select count(1) from table1 join table2 on table1.name = table2.name;
      

      When there are constant values in select list and equi-join keys are text columns, it causes some errors due to schema mismatch.

      Its cause of this bug is as follows:

      • the number 1 results in a generated column name '?literal'.
      • This name is used in both table1 and table2. Output schemas of table1 and table2 include ?literal
      • The input schema of join has only three columns because ?literal is duplicated name.

      So, its essential bug may be one of following:

      • The constant value is evaluated twice. In other words, literal? occurs in both table1 and table2.
      • Schema class does not allow the same column name.

        Attachments

        1. TAJO-619.patch
          16 kB
          Hyunsik Choi

          Activity

            People

            • Assignee:
              hyunsik Hyunsik Choi
              Reporter:
              hyunsik Hyunsik Choi
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              Dates

              • Created:
                Updated:
                Resolved: