We have a query against a view in production which used to run efficiently. However, recent explain plan showed some full table scan in one table which proper index and join with other table in the view.
We indexed the table but it does not seem to fix the issue.
We later locked the stats for that table, and explain plan was showing correct index scan.
Note that the table have new rows inserting every day.

I think locking table stats is not a permanent solution and I think rebuilding index should have updated the stats. So I am confused why it is like that.

create outline my_outline for category my_category
on select [your query]

alter session/system set query_rewrite_enabled=true;
alter session/system set use_stored_outlines=my_category;