Re: proposal: jsonb_populate_array

út 15. 8. 2023 v 5:12 odesílatel jian he <jian(dot)universality(at)gmail(dot)com>
napsal:

> \df jsonb_populate_record
> List of functions
> Schema | Name | Result data type | Argument data
> types | Type
>
> ------------+-----------------------+------------------+---------------------+------
> pg_catalog | jsonb_populate_record | anyelement | anyelement,
> jsonb | func
> (1 row)
>
> manual:
> > anyelement Indicates that a function accepts any data type.
> > For the “simple” family of polymorphic types, the matching and deduction
> rules work like this:
> > Each position (either argument or return value) declared as anyelement
> is allowed to have any specific actual data type, but in any given call
> they must all be the same actual type.
>
> So jsonb_populate_record signature can handle cases like
> jsonb_populate_record(anyarray, jsonb)? obviously this is a cast, it
> may fail.
> also if input is anyarray, so the output anyarray will have the same
> base type as input anyarray.
>

It fails (what is expected - else be too strange to use function in name
"record" for arrays)

(2023-08-15 07:57:40) postgres=# select
jsonb_populate_record(null::varchar[], '[1,2,3]');
ERROR: first argument of jsonb_populate_record must be a row type

regards

Pavel