Обсуждение: [GENERAL] CREATE AGGREGATE on jsonb concat

hi,

We do this in our database:

CREATE AGGREGATE jsonb_collect(jsonb) (
    SFUNC = 'jsonb_concat',
    STYPE = jsonb,
    INITCOND = '{}'
);

Is there some other built-in aggregate I'm missing that would do the
same thing? It just feels like such an obvious feature.

Thanks for your advice,
Seamus

--
Seamus Abshere, SCEA
https://github.com/seamusabshere
https://linkedin.com/in/seamusabshere
https://www.faraday.io

Seamus Abshere <seamus@abshere.net> writes:
> We do this in our database:

> CREATE AGGREGATE jsonb_collect(jsonb) (
>     SFUNC = 'jsonb_concat',
>     STYPE = jsonb,
>     INITCOND = '{}'
> );

> Is there some other built-in aggregate I'm missing that would do the
> same thing? It just feels like such an obvious feature.

Doesn't jsonb_agg() do exactly that?

            regards, tom lane

> Seamus Abshere <seamus@abshere.net> writes:
> > We do this in our database:
>
> > CREATE AGGREGATE jsonb_collect(jsonb) (
> >     SFUNC = 'jsonb_concat',
> >     STYPE = jsonb,
> >     INITCOND = '{}'
> > );
>
> > Is there some other built-in aggregate I'm missing that would do the
> > same thing? It just feels like such an obvious feature.

> On Thu, Jul 6, 2017, at 04:53 PM, Tom Lane wrote:
> Doesn't jsonb_agg() do exactly that?

hi Tom,

That aggregates into an array. Our `jsonb_collect` aggregates into an
object.

Best,
Seamus

Seamus Abshere <seamus@abshere.net> writes:

> That aggregates into an array. Our `jsonb_collect` aggregates into an object.

Postgres 9.6 has (per
https://www.postgresql.org/docs/9.6/static/functions-aggregate.html):

* jsonb_agg(expression)
* jsonb_object_agg(name, value)

In retrospect, I think what I am proposing is:

* jsonb_object_agg(expression)

Is that sane?

Best,
Seamus