php classes and data retrieval

Hello! I have a database and php classes and I'm not sure the best way I should be retrieving the data. as below, if 'other' (line 9) is stored in the database as an id of a record in another table, should my getData() method: a. return the id as part of the MyObj object and whatever function that called it is responsible for matching the id to the name? or b. should it look up the value from within the class? (I read something about JOIN or stuff beyond SELECT --sorry i'm kinda just getting into this-- could bring a database to it's knees) Also I thought that with OOP you are supposed to keep the classes independent of each other, but I was thinking if I need a MyObj I would want all the data in a ready usable form and not a mix of data and database ids. I'm not sure what is the best practice or even if there is a correct one, but suggestions would be appreciated! -robert here is my set up: DATABASE: myobj_table with id, name, other as columns other_table with id, name as columns PHP CLASSES: 1: <?php 2: 3: /* base object data structure */ 4: class MyObj { 5: 6: function MyObj($id, $name, $other) {

   7:     $this->id = $id;
   8:     $this->name = $name;
   9:     $this->other = $other; // ?? ID OR VALUE ??

10: } 11: 12: // getters/setters 13: 14: } 15: 16: 17: /* create/update/delete database methods */ 18: class MyObjData { 19: 20: var $_id; 21: var $_items; 22: 23: function MyObjData($id) {

  24:     $this->_id = $id;

25: } 26: 27: function getData() {

  28:     $query = "select * from myobject_table where id='" . $this-
_id . "'";
  29:     $records = getDatabaseRecords($query); // some db action: returns an array of records

  30:     foreach ($records as $record) {
  31:       $data = new MyObj(
  32:           $record['id']
  33:         , $record['name']
  34:         , $record['other']
  35:         );
  36:       $this->_items[] = $data;
  37:       unset($data);
  38:     }
  39:     return $this->_items;

40: } 41: 42: // other methods 43: 44: } 45: 46: 47: 48: ?>