nerfdhtyersdfher
New Member
I'm using CodeIgniter to build a php web application, and I'm trying to use good OO practices - of which there appears to be many schools of thought. I specifically have a class biography_model to interact with a MySQL table. This data model has some class properties representing the columns in the table, but it also has some properties not in the table such as \[code\]$image_url\[/code\]. The class constructor function accepts an optional record ID parameter which then fetches that record from the table and sets all object properties by calling the \[code\]get_biography()\[/code\] method, including the \[code\]$image_url\[/code\] property not in the table. This way I can instantiate a new biography_model object in the controller with all useful properties ready to go: \[code\]$bio = new biography_model($id);\[/code\]But, what is the best approach when we are returning a multi-row result set of records from the table? For each record I need to also set the \[code\]$image_url\[/code\]. I could do this in the controller, by querying the list of records in the table and then passing each id into the new biography_model($id) object. But then I would have a situation where the controller is directly querying the database bypassing the model. Instead, I choose to return an array of biography_model objects from within the biography_model.Example: \[code\] class Biography_model extends Model { /** * This model manages biography information in the 'biography_content' table. * If a biography ID is passed in when instantiating a new object, * then all class properties are set. */ protected $id; protected $person_name; protected $title; protected $image_file_name; protected $image_url; protected $biography_text; protected $active; /** * Constructor * * If an id is supplied when instantiating a new object, then * all class variables are set for the record. */ public function __construct($person_id = NULL) { parent::Model(); if(isset($person_id)) { $this->set_property('id',$person_id); $this->get_biography(); } } /** * Sets supplied property with supplied value. */ public function set_property($property, $value) { // Set image path if $value is the file name if($property == 'image_file_name') { $this->set_property('image_url',$this->get_bio_img_url($value)); } $this->$property = $value; } /** * Gets requested property value. */ public function get_property($property) { return $this->$property; } /** * Returns the biography thumbnail image URL */ public function get_bio_img_url($image_name) { return $this->config->item('parent_url').'assets/img/biography/'.$image_name; } /** * Get one or more biography entries */ public function get_biography() { // If the ID is set then set model properties. if($this->get_property('id')) { $this->db->where('id',$this->get_property('id')); $query = $this->db->get('biography_content'); if($query->num_rows() == 1) { foreach($query->row() as $key => $value) { $this->set_property($key, $value); } } } // Otherwise return result set of all biographies else { // Get the list of record ID's $this->db->select('id'); $query = $this->db->get('biography_content'); if ($query->num_rows() > 0) { // New array to return result set $biography_list = array(); // For each record, return a new biography_model object foreach($query->result() as $value) { $biography_list[] = new biography_model($value->id); } } return $biography_list; } } } // End of Biography_model Class\[/code\]It works. But is it a reasonable approach? Are there other more accepted methods? I'm keenly aware that I am querying the database twice, but I was not sure of a better way to handle this. All suggestions are welcome!Thanks, Wolf