Re: [HACKERS] Planner creating ineffective plans on LEFT OUTER joins

Simon Riggs wrote:
> IMHO we should have a single parameter which indicates how much planning
> time we consider acceptable for this query. e.g.
> optimization_level = 2 (default), varies 1-3

Couldn't the planner itself make a good guess if it should
keep trying based on the estimated cost?

if (the_best_plan_I_found_so_far_looks_like_itll_take_an_hour)
keep_optimizing_for_a_few_minutes
if (the_best_plan_I_found_so_far_looks_like_itll_take_0.01ms)
stop_planning_and_run_with_it

Or maybe as simple as something like

if (time_spent_planning >= cost_of_the_best_plan_found / 10)
stop_optimizing.

If we wanted a GUC, perhaps make it that 10 in the expression above?

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