function does not exists in postgreSQL .. Why ? - postgresql

Question

Need your help please , can't understand why i got the following error , i am not a professional postgresql developer ..
As you can see the function created , so why the function not exist occurred ?
create or replace function loginAttempt (u_email character varying, u_password character varying, date_time timestamptz, OUT attempt smallint) returns smallint AS $$
BEGIN
INSERT INTO login_attempts (typed_password, date_time, attempt_nu, email) VALUES (u_password, date_time, attempt_nu, email);
IF attempt = 3 THEN INSERT INTO warnings (u_email,u_password) VALUES (u_email,u_password);
END IF;
END;
$$ LANGUAGE plpgsql;
select loginattempt ('Jon.Jones88#gmail.com','+_#kjhfdb987', now(), 1);
ERROR: function loginattempt(unknown, unknown, timestamp with time zone, integer) does not exist
LINE 1: select loginattempt ('Jon.Jones88#gmail.com','+_#kjhfdb987',...
^
HINT: No function matches the given name and argument types. You might need to add explicit type casts.
SQL state: 42883
Character: 8

Answer 1

You have defined the last parameter as an OUT parameter, that means you can't pass a value for it.
You need to use:
select loginattempt ('Jon.Jones88#gmail.com','+_#kjhfdb987', now());
As you are not writing to the parameter attempts I don't see a reason to define it as an out parameter to begin with. You can simply return the value if you need it:
create or replace function loginAttempt (u_email character varying, u_password character varying, u_date_time timestamptz, u_attempt smallint)
returns smallint
AS $$
BEGIN
INSERT INTO login_attempts (typed_password, date_time, attempt_nu, email)
VALUES (u_password, u_date_time, u_attempt, u_email);
IF u_attempt = 3 THEN
INSERT INTO warnings (u_email,u_password) VALUES (u_email,u_password);
END IF;
return u_attempt;
END;
$$ LANGUAGE plpgsql;
As the value 1 is assumed to be an integer, you need to cast that value when calling the function:
select loginattempt ('Jon.Jones88#gmail.com','+_#kjhfdb987', now(), 1::smallint);
Online example: https://rextester.com/YNIQ55561