Re: JSON query help

Gavin Henry <gavin(dot)henry(at)gmail(dot)com> writes:
> This is 9.6 with BDR in.

Um ... I bet not. Maybe you're confusing the version of psql with
that of the server? Because jsonb_build_object() is definitely
there in 9.6.

> ERROR: operator does not exist: jsonb @> json

This one you just need a cast for --- the server won't automatically
convert json to jsonb. (I don't remember why we didn't make that
cast implicit, but probably there was a good reason.)

> How can I check if that function does exist?

On a 9.6 server, you should get

=# \df jsonb_build_object
List of functions
Schema | Name | Result data type | Argument data types | Type
------------+--------------------+------------------+---------------------+--------
pg_catalog | jsonb_build_object | jsonb | | normal
pg_catalog | jsonb_build_object | jsonb | VARIADIC "any" | normal
(2 rows)

If, as I suspect, it's really 9.4, you could substitute
json_build_object(...)::jsonb

regards, tom lane