Re: proposal: searching in array function - array_position - Mailing list pgsql-hackers

From Petr Jelinek
Subject Re: proposal: searching in array function - array_position
Date
Msg-id 54E93856.6070701@2ndquadrant.com
Whole thread Raw
In response to Re: proposal: searching in array function - array_position  (Pavel Stehule <pavel.stehule@gmail.com>)
Responses Re: proposal: searching in array function - array_position  (Pavel Stehule <pavel.stehule@gmail.com>)
List pgsql-hackers
On 28/01/15 08:15, Pavel Stehule wrote:
>
>
> 2015-01-28 0:01 GMT+01:00 Jim Nasby <Jim.Nasby@bluetreble.com
> <mailto:Jim.Nasby@bluetreble.com>>:
>
>     On 1/27/15 4:36 AM, Pavel Stehule wrote:
>
>
>         It is only partially identical - I would to use cache for
>         array_offset, but it is not necessary for array_offsets ..
>         depends how we would to modify current API to support externally
>         cached data.
>
>
>     Externally cached data?
>
>
> Some from these functions has own caches for minimize access to typcache
> (array_map, array_cmp is example). And in first case, I am trying to
> push these information from fn_extra, in second case I don't do it,
> because I don't expect a repeated call (and I am expecting so type cache
> will be enough).
>

You actually do caching via fn_extra in both case and I think that's the 
correct way, and yes that part can be moved common function.

I also see that the documentation does not say what is returned by 
array_offset if nothing is found (it's documented in code but not in sgml).


--  Petr Jelinek                  http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training &
Services



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