Delphi/FireDac + PostgreSQL + stored procedure + Procedure (To call a procedure, use CALL) - postgresql

Question

We are putting postgreSQL database support on our system, we currently work with Oracle.
We are trying to call a procedure in the database, just as we call in Oracle.
var conBanco := TFDConnection.Create(Self);
try
conBanco.Params.Database := 'Database';
conBanco.Params.UserName := 'UserName';
conBanco.Params.Password := 'Password';
conBanco.Params.Values['Server'] := 'IP';
conBanco.Params.DriverID := 'PG';
conBanco.Open();
var stpBanco := TFDStoredProc.Create(Self);
try
stpBanco.Connection := conBanco;
stpBanco.StoredProcName := 'gerador_padrao';
stpBanco.Prepare;
stpBanco.ParamByName('gerador').Value := 'pessoas';
stpBanco.ExecProc();
ShowMessage(VarToStrDef(stpBanco.ParamByName('parchave').Value, ''));
finally
stpBanco.Free;
end;
finally
conBanco.Free;
end;
However we get the following error:
exception class : Exception
exception message : EPgNativeException: [FireDAC][Phys][PG][libpq]
ERROR: superus.gerador_padrao(gerador => character varying, parchave
=> numeric) is a procedure. To call a procedure, use CALL.
Stored procedure in database:
CREATE OR REPLACE PROCEDURE superus.gerador_padrao
(gerador character varying, INOUT parchave numeric)
LANGUAGE plpgsql
AS $procedure$
begin
--Code
end;
$procedure$
;
The error occurs on the following line:
stpBanco.Prepare;
The above code works perfectly in Oracle, how do I call the procedure in PostgreSQL?
Thank you.

Answer 1

Below we will talk about Delphi 10.2.3, maybe in later versions it's different.
Inside the file FireDAC.Phys.PGMeta.pas has a TFDPhysPgCommandGenerator.GetStoredProcCall method, inside which the procedure text is formed and there is no option to call the procedure via CALL. Moreover, there is no "CALL " text in this entire file. Maybe this is a mistake, or maybe some kind of cunning idea... But that doesn't make it any easier for us.
// function returns void
if not lHasOut then begin
if FCommandKind = skStoredProc then
FCommandKind := skStoredProcNoCrs;
// NULL to avoid problem with execution of a
// void function in binary result format
Result := 'SELECT NULL FROM ';
end
else begin
if lHasCrs and (FCommandKind = skStoredProc) then
FCommandKind := skStoredProcWithCrs
else if lFunc then
lFunc := FCommandKind in [skStoredProc, skStoredProcNoCrs];
if lFunc then
Result := 'SELECT '
else
Result := 'SELECT * FROM ';
end;
In total, here I see 2 options:
Form the procedure call string yourself. I'm sure it's not difficult, although, of course, it's more correct when the component does it.
Instead of a procedure, make a function with the same content, and make your output parameter the result. It is important to remember - the procedure call then must pass through ExecFunc in this case;