Re: WIP: Range Types

* Jeff Davis:

> On Tue, 2011-01-04 at 14:18 +0000, Florian Weimer wrote:
>> * Jeff Davis:
>>
>> > 4. For the GiST penalty function, and perhaps some picksplit algorithms,
>> > it might be nice to know the length of a range, or do some other kinds
>> > of math. It introduces a lot of complexity to try to define math
>> > functions for each subtype, and try to make sure they behave sanely. So
>> > I was thinking that the user might need to specify a function that
>> > converts the subtype into a float that approximates a value's position
>> > in the total order.
>>
>> Doesn't the eqsel hint already provide this information?

> Can you clarify what you mean? I don't know what the "eqsel hint" is.

Uhm, it's not not eqsel, but the RESTRICT clause on operators:

<http://www.postgresql.org/docs/8.4/static/xoper-optimization.html>

I'm wondering if one of these hint functions can be reused to compute
range lengths.

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