AUTO_STAT_MODE configuration parameter

Use the AUTO_STAT_MODE configuration parameter to enable or disable the mode for selectively updating only stale or missing data distributions in UPDATE STATISTICS operations instead of updating statistics for all data distributions.

onconfig.std value
Not set. If the AUTO_TUNE configuration parameter is set to 1, statistics are updated selectively.
values
0 = Disables selective UPDATE STATISTICS operations.

1 = Enables selective UPDATE STATISTICS operations.

takes effect
After you edit your onconfig file and restart the database server.
When you reset the value dynamically in your onconfig file by running the onmode -wf command.
When you reset the value in memory by running the onmode -wm command.
If an AUTO_STAT_MODE value is not set in your current onconfig file and you set the AUTO_TUNE configuration parameter.

Usage

When the AUTO_STAT_MODE configuration parameter or the AUTO_STAT_MODE session environment variable have enabled the automatic mode for selectively updating only stale or missing data distributions in UPDATE STATISTICS operations, the database server uses the value of the STATCHANGE configuration parameter to identify table or fragment distribution statistics that need to be updated.

In sessions where the AUTO_STAT_MODE configuration parameter and the AUTO_STAT_MODE session environment variable have different settings, the session environment variable takes precedence for the duration of that session, or until the AUTO_STAT_MODE session environment variable is reset.


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