We are on oracle 18.104.22.168 on a highly OLTP database and looking to improve overall performance using init.ora parameters. Currently optimizer_index_cost_adj is 100. Is this good to keep 100 or it is better to test with a lower value like 25 ? I remember using it on old 9i and 10g databases. Is this still a good parameter to look or just leave this alone?
What is expert's advise on it?