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  1. MariaDB Server
  2. MDEV-20609

Full table scan in INFORMATION_SCHEMA.PARAMETERS/ROUTINES

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      It seems there is an issue when querying on I_S.PARAMETERS table (used in java metadata) :
      when doing this kind of query (one result) :
      SELECT * FROM INFORMATION_SCHEMA.PARAMETERS WHERE SPECIFIC_SCHEMA = 'testj' AND SPECIFIC_NAME = 'p2_512'
      It takes 15ms if 400 parameters in I_S.PARAMETERS table
      It takes 65ms if 4K parameters
      It takes 350ms if 20K parameters

      It seems to execute a full table scan in INFORMATION_SCHEMA.PARAMETERS

      The same query takes 6ms on mysql 8 with 20K same parameters

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              oleg.smirnov Oleg Smirnov
              diego dupin Diego Dupin
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