Re: Variant (Untyped) parameter for function/procedure

On 6/5/24 01:34, Durumdara wrote:
> Dear Members!
>
> As I experienced, the functions/procedures extremely depend on
> parameters (very typed).
> So if I have to restructure the input parameters, I can't modify the
> function, because I have to recreate the dependents too.
> For example:
> I have a type. If I pass this type to a function, I can't change the
> structure of the type without dropping and recreating the function.
>
> create type blahtype as (a int, b bool);
> create function blahcheck (input blahtype) ...
>
>
> If I have many dependent functions this causes that I have to drop
> (recreate) everything - just for an extra parameter. And sometimes this
> extra parameter doesn't change 10 functions, only one. But I have to
> recreate them all (without changing the body).
>
> Is there any way to use a Variant parameter?

You mean like:

https://www.postgresql.org/docs/current/extend-type-system.html#EXTEND-TYPES-POLYMORPHIC

Examples here:

https://www.postgresql.org/docs/current/plpgsql-declarations.html#PLPGSQL-DECLARATION-PARAMETERS

Starting at:

"... When the return type of a PL/pgSQL function is declared as a
polymorphic type ..."

Or there is VARIADIC:

https://www.postgresql.org/docs/current/xfunc-sql.html#XFUNC-SQL-VARIADIC-FUNCTIONS

> Like this:
>
> create procedure test(IN Input Record, OUT Output Record)
> ...
>     Time = Input.Time::timestamp;
> ...
>
>     Output = SomeHowMakeItTyped;
>
>     Output.Result = 1;
>
> ...
>
>
> Caller:
>
> ...
> for r_in as select  id, name from blah into
> ...
>      test(r_in, r_out);
>      if r_out.result <> 0 then ...
>
> Or:
>
> create procedure test(IN Inputs Records, OUT Output Record)
> ...
>         for Input in Inputs:
>         Time = Input.Time::timestamp;
> ...
>     Output.Result = 1;
> ...
>
>
>
>
> Or is it impossible, because of the PGSQL's philosophy (very typed)?
>
> If it is not possible then I have one way I think.
> It is a JSON data type for inputs and outputs.
>
> Is that right?
>
> Thanks for your any help, info!
>
> Best regards
> dd
>
>
>
>
>

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com