We have a 12c db that runs an ERP app. We face slowness with some processes
- Upon analysis we created some indexes and re ran the processes. A few of
the processes would not complete - the optimizer would not use the index.
We adjusted the OIC/OICA (idxCachg/idxCostAdj) - with new values several of
the reports completed. However some other processes do not complete even
after an hour. But they complete ok with the older values of oic/oica. Many
of the SQLs are generated dynamically, so using hints is not an option.
It looks like we can work with adjusting the values of oic/oica for
different processes. However many of these users could run the processes at
the same time. My limited research shows that oic/oica have an effect on
the access paths and eventually the cost of the query; read wolfgang's
paper on the subject. I am sure I am not the only person who faced this
problem. Any ideas on how to approach the issue? Thanks a lot.