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  1. MariaDB Server
  2. MDEV-20854

ANALYZE for statements: not clear where the time is spent

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      Description

      ANALYZE FORMAT=JSON shows r_total_time_ms field which allows one to see where the time was spent during execution.

      r_total_time_ms is provided for

      • query_block, aka a SELECT
      • table, individual table references
      • filesort node.
      • ...

      The issue is that for many-table join one can frequently see that

      • The join itself (query_block) took a lot of time
      • table access in the join add up to a fraction of time.

      this leaves one puzzled re where the time is spent.
      An example of such case is MDEV-20646.

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            Assignee:
            Unassigned
            Reporter:
            psergey Sergei Petrunia
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              Updated:
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