Hi,

some of our parallel direct path insert Statements suffer from enq: HV contention.
These are big, straight forward inserts. Contention can be up to 60% of the db time.
We did some tests and realized that temp Segment merge would get rid of the issue.
(No surprise).
We can save hours on our ETL process.
For the tests we changed the Settings of "_insert_enable_hwm_brokered" and "_px_hybrid_TSM_HWMB_load" on the System Level (alter System).

However we want to Switch on temp Segment merge only for certain selected Statements, for the rest we want to Keep the Default.

That does not seem to be possible. Whilest opt_param('_px_hybrid_TSM_HWMB_load','false') changes the behaviour from Hybrid TSM/HWB to brokered load, we can not see any effect from the hint
opt_param('_insert_enable_hwm_brokered','false').

Ok, it is questionable if this is an optimizer Parameter..
Still: how can we get temp Segment merge for selected Statements? Is there some Switch control?