So I am going to change join_collapse_limit and from_collapse_limit to 20. Do I need to set geqo_threshold to greater than 20. Now it is 12 ( default).
And could you let me know why geqo_optimizer is not working good in this case? On Fri, Dec 14, 2012 at 2:22 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: > "Kevin Grittner" <kgri...@mail.com> writes: > > AI Rumman wrote: > >> Does FK Constraint help to improve performance? Or it is only > >> for maintaining data integrity? > > > I'm not aware of any situation where adding a foreign key > > constraint would improve performance. > > There's been talk of teaching the planner to use the existence of FK > constraints to improve plans, but I don't believe any such thing is > in the code today. > > regards, tom lane >
