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  1. MariaDB Server
  2. MDEV-5118

Explain output for SHOW EXPLAIN in the slow log looks useless

        Details

        • Type: Bug
        • Status: Open
        • Priority: Trivial
        • Resolution: Unresolved
        • Affects Version/s: 10.0.10
        • Fix Version/s: 10.0
        • Component/s: None
        • Labels:
          None

          Description

          In all attempts, I was never able to get any other "plan" than this for SHOW EXPLAIN in the slow log:

          # Time: 131009 20:35:29
# User@Host: root[root] @ localhost [127.0.0.1]
# Thread_id: 6  Schema: test  QC_hit: No
# Query_time: 0.002340  Lock_time: 0.000849  Rows_sent: 1  Rows_examined: 1
#
#  id   select_type     table   type    possible_keys   key     key_len ref     rows    Extra
#  1    SIMPLE  EXPLAIN ALL     NULL    NULL    NULL    NULL    NULL    
#
SET timestamp=1381336529;
show explain for 4;

          If it's really going to be always the same, maybe it doesn't make sense to print it there at all.

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                relates to

                Task - A task that needs to be done. MDEV-407 Print EXPLAIN [ANALYZE] in the slow query log

                • Major - Major loss of function.
                • Closed

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                  psergey Sergei Petrunia added a comment -

                  I suspect this is because they've made me to re-implement SHOW EXPLAIN as a SELECT from an I_S table.

                  There can be other kinds statements that do not really have query plans. Perhaps, log_slow_verbosity=explain should not print EXPLAINs that are trivial.

                  Show
                  psergey Sergei Petrunia added a comment - I suspect this is because they've made me to re-implement SHOW EXPLAIN as a SELECT from an I_S table. There can be other kinds statements that do not really have query plans. Perhaps, log_slow_verbosity=explain should not print EXPLAINs that are trivial.

                    People

                    • Assignee:
                      psergey Sergei Petrunia
                      Reporter:
                      elenst Elena Stepanova
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                      Dates

                      • Created:
                        Updated: