Uploaded image for project: 'Flink'
  1. Flink
  2. FLINK-7403

Remove expandLocalRef() before code generation

    XMLWordPrintableJSON

Details

    • Improvement
    • Status: Open
    • Major
    • Resolution: Unresolved
    • None
    • None
    • Table SQL / Planner
    • None

    Description

      Currently, we expand local references before code generation. This means that expressions that actually only need to be evaluated once, might be evaluated multiple times. We should remove the expand step where possible.
      Take the following query as an example:

      t.select(func0('c), func0('c), func0('c))

      func0('c) is called three times for every input row even func0 is deterministic. It would be nice if we can reuse it.

      Attachments

        Issue Links

          is related to

          Bug - A problem which impairs or prevents the functions of the product. FLINK-10834 TableAPI flatten() calculated value error

          • Minor - Minor loss of function, or other problem where easy workaround is present.
          • Open

          Activity

            People

              Unassigned Unassigned
              twalthr Timo Walther
              Votes:
              0 Vote for this issue
              Watchers:
              4 Start watching this issue

              Dates

                Created:
                Updated: