Re: [COMMITTERS] pgsql: Install some slightly realistic cost

Tom Lane wrote:
> > It will also keep long lists of ORs from turning what would have been
> > a >10% index scan into a seq scan, yes?
>
> It should look more attractive than the old method, yes. At some point
> you still end up deciding you might as well seqscan. I'm not sure
> whether the cost estimation model I put in last night gets the crossover
> point right --- we'll need to get some field experience as soon as the
> code is reasonably functional.
>
> That reminds me: at least for testing purposes, it'd be a good idea
> to have an additional planner "enable" switch for this plan type,
> analogous to enable_seqscan and enable_indexscan. Any objections to
> adding one? Should I call it "enable_bitmapscan", or can someone
> think of a less ugly name?

I think "enable_bitmapscan" is the best we can do.

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