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  1. Phoenix
  2. PHOENIX-2702

Show estimate rows and bytes touched in explain plan.

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Details

    • Bug
    • Status: Resolved
    • Major
    • Resolution: Fixed
    • None
    • 4.7.0
    • None
    • None

    Description

      We can already estimate the size of a table (both rows and uncompressed bytes) with q query like this:

      SELECT physical_name AS table_name, SUM(guide_posts_row_count) AS est_rows, SUM(guide_posts_width) AS est_size from SYSTEM.STATS GROUP BY physical_name;
      

      During the planning phase we have more information, though. So we can report the actual numbers for a query during an explain since we have that info there anyway (we filtered the guidepost already with the key info provided in the query).

      I might whip up a quick patch for this.
      (Could also go further and add a est_count, est_size UDF for this, but that would be a bit harder to get hooked up at the right places, I think, and the meaning would be ambiguous)

      Attachments

        1. PHOENIX-2702.txt
          4 kB
          Lars Hofhansl

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            larsh Lars Hofhansl
            larsh Lars Hofhansl
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            Dates

              Created:
              Updated:
              Resolved: