APEX

Does anyone have any documentation on what happens in the following Apex scheduler processes:

wwv_flow_maint.daily_maintenance
wwv_flow_cache.purge_sessions

There are two other ones as well, but I suspect one of these contains what I'm looking for.

As background, running Apex 4.0. We are having issues with the collection table statistics. When the tables have statistics (after reports using collections have been run) the reports run in a timely manner. However, over the weekend, when no one is running the reports, statistics are run against the collections tables (wwv_flow_collections$ and wwv_flow_collection_members$) and revert the row counts to 0. Come Monday morning, the queries run abnormally slow since the optimizer thinks the tables are emptly.

I would like to be able to generate statistics on the tables and NOT have them wiped out by some scheduler job. Just trying to figure out which one it is, as I will likely have to put in place a "counter" job to import statistics after the built-in job runs.

Thanks.