I know that in OOP you want every object (from a class) to be a "thing", eg. user, validator etc.

I know the basics about MVC, how they different parts interact with each other.

However, i wonder if the models in MVC should be designed according to the traditional OOP design, that is to say, should every model be a database/table/row (solution 2)?

Or is the intention more like to collect methods that are affecting the same table or a bunch of related tables (solution 1).

example for an Address book module in CodeIgniter, where i want be able to "CRUD" a Contact and add/remove it to/from a CRUD-able Contact Group.

Models solution 1: bunching all related methods together (not real object, rather a "package")

class Contacts extends Model {

     function create_contact() {)
     function read_contact() {}
     function update_contact() {}
     function delete_contact() {}

     function add_contact_to_group() {}
     function delete_contact_from_group() {}

     function create_group() {}
     function read_group() {}
     function update_group() {}
     function delete_group() {}

}

Models solution 2: the OOP way (one class per file)

class Contact extends Model {
     private $name = '';
     private $id = '';

     function create_contact() {)
     function read_contact() {}
     function update_contact() {}
     function delete_contact() {}

}

class ContactGroup extends Model {
     private $name = '';
     private $id = '';

     function add_contact_to_group() {}
     function delete_contact_from_group() {}

     function create_group() {}
     function read_group() {}
     function update_group() {}
     function delete_group() {}

}

i dont know how to think when i want to create the models. and the above examples are my real tasks for creating an Address book. Should i just bunch all functions together in one class. then the class contains different logic (contact and group), so it can not hold properties that are specific for either one of them.

the solution 2 works according to the OOP. but i dont know why i should make such a dividing. what would the benefits be to have a Contact object for example. Its surely not a User object, so why should a Contact "live" with its own state (properties and methods).

you experienced guys with OOP/MVC, please shed a light on how one should think here in this very concrete task.