If you use DBMS_STATS.GATHER_SCHEMA_STATS or DBMS_STATS.GATHER_DATABASE_STATS with options=> ‘GATHER AUTO’ then the preferences for the tables whose statistics are gathered are ignored.
See this testcase which includes a SQL*Plus script and log demonstrating that GATHER_SCHEMA_STATS ignores a preference. I’ve seen the same thing with GATHER_DATABASE_STATS but it wasn’t as quick to build a test case.
So, if you depend on table preferences don’t use GATHER AUTO.
– Bobby
