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  1. MariaDB Server
  2. MDEV-6356

QUERY CACHE - Query Cache And Autocommit

        Details

        • Type: Bug
        • Status: Open
        • Priority: Minor
        • Resolution: Unresolved
        • Affects Version/s: 5.1.67, 5.2.14, 5.3.12, 5.5.38, 10.0.12
        • Fix Version/s: 5.3.13, 10.0, 5.5
        • Component/s: None

          Description

          I was using Maria 10.0.10 today and was banging my head against a wall for a few hours trying to figure out why my queries were missing the query cache.

          http://bugs.mysql.com/bug.php?id=42197

          I am working on a legacy PERL project that spawns many short-lived processes that connect to the database and do a single query before exiting.

          my $dsn = "dbi:mysql:database=test";
my $dbh = DBI->connect($dsn, undef, undef, {RaiseError => 0, AutoCommit => 0});

# 1. Prepare query
# 2. Executed query (misses cache)
# 3. Process result

          When DBI connects to the SQL server, the first thing it does is issue the "SET" command and then the query comes quickly behind it:

          SET AUTOCOMMIT=0;
SELECT * FROM test;

          When it then executes its query, it misses the query cache every time.

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                Issue Links

                links to

                Web Link Bug #42197 - Query cache and autocommit

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                  rspadim roberto spadim added a comment -

                  the problem is autocommit and begin are part of flags that make a query unique, check documentation:
                  https://mariadb.com/kb/en/mariadb/documentation/optimization-and-tuning/buffers-caches-and-threads/query-cache/

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                  rspadim roberto spadim added a comment - the problem is autocommit and begin are part of flags that make a query unique, check documentation: https://mariadb.com/kb/en/mariadb/documentation/optimization-and-tuning/buffers-caches-and-threads/query-cache/

                    People

                    • Assignee:
                      Unassigned
                      Reporter:
                      belugabehr BELUGABEHR
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                      Dates

                      • Created:
                        Updated: