Re: json api WIP patch

On Fri, Feb 1, 2013 at 6:03 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Daniel Farina <daniel@heroku.com> writes:
>> On Fri, Feb 1, 2013 at 2:08 PM, Robert Haas <robertmhaas@gmail.com> wrote:
>>> I think it's smarter for us to ship functions, and let users wrap them
>>> in operators if they so choose.  It's not difficult for people who
>
>> The problem being: even though pg_operator resolves to functions in
>> pg_proc, they have distinct identities as far as the planner is
>> concerned w.r.t selectivity estimation and index selection.
>
> Yeah, this is surely not a workable policy unless we first move all
> those planner smarts to apply to functions not operators.  And rewrite
> all the index AM APIs to use functions not operators, too.  Now this is
> something that's been a wish-list item right along, but actually doing
> it has always looked like a great deal of work for rather small reward.

Hmm.  Well, if the operators are going to be indexable, then I agree
that's an issue, but isn't -> just a key-extraction operator?  That
wouldn't be something you could index anyway.

-- 
Robert Haas
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