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Disabling optimizer dynamic sampling

Dynamic sampling is a functionality that gathers statistics on the fly during query execution. When switched on, it can adversely affect performance. For that reason, you should ensure that the SYS user disables optimizer dynamic sampling in the Oracle database.

Procedure

  1. Open a command shell for your operating system.
  2. Start SQLPlus by entering the following on the command prompt: sqlplus SYS AS SYSDBA
  3. Enter the following command:
    ALTER SYSTEM SET optimizer_dynamic_sampling=0