--Explicit procedure 

create or replace procedure get_emp_names(dept_num IN number) 
is
emp_name employees.first_name%type;
cursor c1 (deptno number) is
select first_name from employees
where department_id=dept_num;
begin
open c1(dept_num);
loop
fetch c1 into emp_name;
exit when c1%notfound;
dbms_output.put_line(emp_name);
end loop;
close c1;
end;

--Explicit call

begin
get_emp_names(50);
end;


--Implicit Procedure

create or replace procedure get_dept_name(dept_num IN number, dept_name OUT departments.department_name%type) 
is

begin
select department_name into dept_name from departments
where department_id=dept_num;
end;

--Implicit Call

declare
d_name departments.department_name%type;
begin
get_dept_name(60,d_name);
dbms_output.put_line('the department name is ' || d_name);
end;


--Get Value from keyboard with apex

declare
name varchar2(20):=:Enter_name;
begin
dbms_output.put_line('Hello ' || name);
end;