Adding additional data to select query result - php

Question

I am fetching data from Articles table but I want to extend returned result with some data from another table.
For example:
public function getArticlesByCategoryId($category_id = 0) {
$select = $this->_db->select()
->from($this->_name)
->limit(5)
->order("pubDate DESC");
$result = $this->_db->fetchAll($select);
$mCategories = new Model_Categories();
foreach($result as $row) { // as &$row doesn't work
$category_name = $mCategories->getNameById($row["category_id"]);
$row["category_name"] = $category_name; // this to add to $result but dunno how
// blah blah...
}
return $result; // the new one with ...->category_name in it.
}
I hope you could understand what I am looking for.
Or maybe it is better to write a single query (with joins, don't know how) and fetch all the data needed in once without calling methods from another Models?

Answer 1

This indeed looks like you should use a join. This definitely is the easiest way to solve your problem. The following query would do the trick:
$select = $this->_db->select()
->from($this->_name)
->join('category_table', 'category_table.id = ' . $this->_name . '.category_id', array('category_name'))
->limit(5)
->order("pubDate DESC");
This will add the category name to the row.
In case you don't want to use a join, you can add a custom field to your row by using a custom row class. This however requires a bit more work. Create the class as follows:
class MyApp_Model_Row_MyRow extends Zend_Db_Table_Row_Abstract
{
public $categoryName;
}
Then you should indicate in your DbTable class that you want to use this new row class:
class MyApp_Model_DbTable_Articles extends Zend_Db_Table_Abstract
{
...
protected $_rowClass = 'MyApp_Model_Row_MyRow';
}
You can then set the category name in a fetched row.

Answer 2

To get all articles with data from your category table your query could look like:
$select = $this->_db->select()
->from($this->_name)
->joinLeftUsing('category','category_id', array('category_name'))
->order("pubDate DESC");
See also: http://framework.zend.com/manual/en/zend.db.select.html