Hello,
I have a DB where x$ksppcv.ksppstvl shows TRUE for both "_optimizer_skip_scan_enabled" and "_gby_hash_aggregation_enabled", but in 10053 trace files I made I see the following:
PARAMETERS WITH ALTERED VALUES
******************************
Compilation Environment Dump
...
_optimizer_skip_scan_enabled = false
_gby_hash_aggregation_enabled = false
...
Outline Data:
/*+
BEGIN_OUTLINE_DATA
IGNORE_OPTIM_EMBEDDED_HINTS
OPTIMIZER_FEATURES_ENABLE('19.1.0')
DB_VERSION('19.1.0')
OPT_PARAM('_unnest_subquery' 'false')
OPT_PARAM('_optimizer_skip_scan_enabled' 'false')
OPT_PARAM('_gby_hash_aggregation_enabled' 'false')
...
??
(this is the database where making a histogram on a certain column has been causing very painful performance issues for a while...)
Thanks.
Regards,
Sebino