Re: index paths and enable_indexscan - Mailing list pgsql-hackers

From Tom Lane
Subject Re: index paths and enable_indexscan
Date
Msg-id 18423.1586874850@sss.pgh.pa.us
Whole thread Raw
In response to Re: index paths and enable_indexscan  (Amit Langote <amitlangote09@gmail.com>)
List pgsql-hackers
Amit Langote <amitlangote09@gmail.com> writes:
> I was really thinking of this in terms of planner effort, which for
> creating an index path is more than creating sequential path, although
> sure the payoff can be great. That is, I want the planner to avoid
> creating index paths *to save cycles*, but see no way of making that
> happen.  I was thinking disabling enable_indexscan would do the trick.

I think that's completely misguided, because in point of fact nobody
is going to care about the planner's performance with enable_indexscan
turned off.  It's not an interesting production case.

All of these enable_xxx switches exist just for debug purposes, and so
the right way to think about them is "what's the simplest, least
bug-prone, lowest-maintenance way to get the effect?".

Likewise, I don't actually much care what results you get if you turn
off *all* of them.  It's not a useful case to spend our effort on.

            regards, tom lane



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