Re: Why no jsonb_exists_path()?

On 06/09/2015 02:40 PM, Tom Lane wrote:
> Josh Berkus <josh(at)agliodbs(dot)com> writes:
>> I'm noticing a feature gap for JSONB operators; we have no way to do this:
>> jsonb_col ? ARRAY['key1','key2','key3']
>> ... that is, there is no way for us to check for key existence in an
>> indexable fashion. Given that @> already can check the whole path
>> including the value, is there some challenge to stopping just short of
>> the value I'm not seeing? Or is this just a "didn't get to it yet" issue?
> Hm, well, the jsonb_path_ops opclass couldn't do it, because what it
> indexes is hashes that include the value. I suppose jsonb_ops could
> look for entries that match all of the keys and then see if the ordering
> is correct.
>
>

It looks to me like we'd need to index all paths in a document, or
possibly hashes of all paths in a document. I don't think anything we
have now will help much, unless my understanding is way off.

cheers

andrew