Re: Calling json_* functions with JSONB data

On Mon, May 23, 2016 at 12:55 PM, Peter van Hardenberg <pvh(at)pvh(dot)ca> wrote:

> Hi there,
>
> I noticed it was very easy to accidentally call the json_* form of JSON
> manipulation functions with jsonb data as input. This is pretty
> sub-optimal, since it involves rendering the jsonb then reparsing it and
> calling the json_* form of the function.
>
> Fortunately, this seems quite easy to resolve by taking advantage of our
> ability to add json_*(jsonb) form of the functions.
>
> I talked this over with Andrew who had no objections and suggested I float
> it on the list before writing a patch. Looks pretty straightforward, just a
> few new data rows in pg_proc.h.
>
> Anyone have any concerns or suggestions?
>
>
Please provide an example of what you are talking about.

SELECT json_array_length('[1,2]'::jsonb)
ERROR: function json_array_length(jsonb) does not exist

-- The function name is "jsonb_array_length"; and there is no implicit cast
between the two.

David J.