Re: Range Types, discrete and/or continuous

On Tue, Oct 26, 2010 at 1:26 PM, Jeff Davis <pgsql(at)j-davis(dot)com> wrote:
> On Mon, 2010-10-25 at 21:07 -0400, Robert Haas wrote:
>> See, that gets complicated, because now you're restricting the range
>> of values that can be expressed by the range type to something less
>> than the natural range of the data type.  I am not sure the value of
>> supporting that is sufficient to justify the amount of extra code that
>> will be required to make it work.  I'd say for a first version, nail
>> down the representation.  Perhaps in a future version you could have
>> compress/uncompress methods sort of like GIST,
>
> OK, I can live with that.
>
>> ALTER TYPE timestamptz
>>     ADD INTERFACE increment timestamp_pl_interval(timestamptz, interval),
>>     ADD INTERFACE decrement timestamp_mi_interval(timestamptz, interval);
>
> I think we chatted about this before. Sounds like a good idea to me
> (except the name -- "increment" is not the same as "plus").
>
> However, this is orthogonal, I think. I can always ask the user to
> specify everything when creating a Range Type, and then we can make them
> default to use the interface functions later. Some, like "plus" might be
> constant, but people certainly might want to specify alternate
> comparators.

If it were me, I would go design and implement the type interface part
first. But it's not.

--
Robert Haas
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