Re: generalizing the planner knobs - Mailing list pgsql-hackers

> In the extreme, no amount of added intelligence in the optimizer is going to
> help it come up with any sane selectivity estimate for something like 
> 
>   WHERE radius_authenticate(user) = 'OK'

Why not?

The missing capability in this case is to be able to provide or generate
(self learning?) statistics for a function that describe a typical
result and the cost of getting that result.
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