Member function and member procedure inside an object type in Oracle.

Question

Hi All,
Please do have a look at these codes and help me understand. I have no idea about this member function and member procedure. How do they work? Please explain me about this.
Regards,
BS2012
create type foo_type as object (
  foo number,
  member procedure proc(p in number),
  member function  func(p in number) return number
create type body foo_type as
  member procedure proc(p in number) is begin
    foo := p*2;
  end proc;
  member function func(p in number) return number is begin
    return foo/p;
  end func;
end;
/

Answer 1

Methods are just like functions or procedures in a package, except they're not in a package, their part of an object type.
The object has attributes (which are the variables declared in it).
To use such an object you would do things like this...
SQL> set serverout on
SQL>
SQL> declare
  2    v_foo foo_type;
  3    v_val number;
  4  begin
  5    v_foo := foo_type(20); -- instantiate the object and initialize the object attributes
  6    v_foo.proc(20); -- call the object method (proc)
  7    v_val := v_foo.func(4); -- call the object method (func)
  8    dbms_output.put_line(v_val);
  9  end;
10  /
10
PL/SQL procedure successfully completed.The Type definition you've declared creates the object class, but not actually an object itself.
To actually have an object you need to declare a variable of that object class type, and then instantiate it. When you instantiate the object you need to initialize all the attributes (generally you can pass null if required for each of them to initialize them).
Once you have your object instantiated, you can call the methods within that object as demonstrated above, a bit like calling functions and procedures in a package, except they are methods within the object type itself, and therefore called directly by referencing them from the variable.
The documentation goes into a lot more detail of objects if you look it up.