AUTO_SAMPLE_SIZE is every row

From: Matt Adams <MAdams_at_equian.com>
Date: Wed, 17 Jan 2018 16:19:35 +0000
Message-ID: <c4a27caf03fb489d91bbbdab12dc9501_at_wpvl1dag04.hcrec.com>

A previous DBA set up all our stats analyzation jobs to be of the form.

BEGIN DBMS_STATS.GATHER_SCHEMA_STATS(ownname => 'FRED', estimate_percent => DBMS_STATS.AUTO_SAMPLE_SIZE, cascade => TRUE ); END;

But for every table I can see, the SAMPLE_SIZE is the same as NUM_ROWS, which is the same as the actual number of rows in the table.

I read somewhere that actual value of AUTO_SAMPLE_SIZE can vary from release to release (and patch to patch), but why on earth would it always be every row in the table?

I'm getting ready to change the estimate percentage to something more reasonable. Just wondering if there is something I'm missing somewhere that is influencing this behavior.

Matt
**** This communication may contain privileged and/or confidential information. If you are not the intended recipient, you are hereby notified that disclosing, copying, or distributing of the contents is strictly prohibited. If you have received this message in error, please contact the sender immediately and destroy any copies of this document. ****

--
http://www.freelists.org/webpage/oracle-l

Received on Wed Jan 17 2018 - 17:19:35 CET