Re: GIN improvements part2: fast scan

On Tue, Jun 25, 2013 at 2:20 AM, Alexander Korotkov <aekorotkov(at)gmail(dot)com>wrote:

> 4. If we do go with a new function, I'd like to just call it "consistent"
>> (or consistent2 or something, to keep it separate form the old consistent
>> function), and pass it a tri-state input for each search term. It might not
>> be any different for the full-text search implementation, or any of the
>> other ones for that matter, but I think it would be a more understandable
>> API.
>
>
> Understandable API makes sense. But for now, I can't see even potentional
> usage of third state (exact false).
>

Typo here. I meant "exact true".

> Also, with preConsistent interface "as is" in some cases we can use old
> consistent method as both consistent and preConsistent when it implements
> monotonous boolean function. For example, it's consistent function for
> opclasses of arrays.
>

Now, I got the point of three state consistent: we can keep only one
consistent in opclasses that support new interface. exact true and exact
false values will be passed in the case of current patch consistent; exact
false and unknown will be passed in the case of current patch
preConsistent. That's reasonable.

------
With best regards,
Alexander Korotkov.