Details

    • Type: Improvement Improvement
    • Status: Open
    • Priority: Major Major
    • Resolution: Unresolved
    • Affects Version/s: 0.9.0
    • Fix Version/s: None
    • Component/s: None
    • Labels:
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      Description

      MergeForEach rule will not merge two consecutive ForEach if the second ForEach has inner relational plan. This prevent some optimizations. Eg,

      A = LOAD 'input1' AS (a0, a1, a2);
      B = LOAD 'input2' AS (b0, b1, b2);
      C = cogroup A by a0, B by b0;
      D = foreach C { E = limit A 10; F = E.a1; G = DISTINCT F; generate group, COUNT(G);};
      explain D;
      

      We add ForEach after cogroup to prune B, however, we cannot merge this ForEach with D. Secondary key optimization for this query is thus disabled.

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          • Assignee:
            Daniel Dai
            Reporter:
            Daniel Dai
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            Dates

            • Created:
              Updated:

              Development