WHERE IN sql query using Zend_Db - zend-framework

Question

Zend Framework beginner here. I'm trying to fetch all the Xbox titles of a video game database. One table contains games. Another table contains game types (ie. Xbox, Xbox Live Arcade, ...). I normally use the following query to get the Xbox titles.
How can I execute the same query using Zend_Db?
Thanks,
SELECT titleGame
FROM Game
WHERE idGameType IN (
SELECT idGameType
FROM GameType
WHERE nameGameType = 'Xbox')

Answer 1

That could be rewritten in Zend Framework a few ways. Here is the way I typically write selects like that using Zend_Db_Table_Select.
<?php
// For brevity, $dbTable = a Zend_Db_Table object
// first construct the subquery/join for the IN clause
// SELECT idGameType FROM GameType HERE nameGameType = 'Xbox'
$subselect = $dbTable->select()
->from('GameType', array('idGameType'))
->where('nameGameType = ?', 'Xbox'); // quotes Xbox appropriately, prevents SQL injection and errors
// construct the primary select
// SELECT titleGame FROM Game WHERE idGameType IN (subquery)
$select = $dbTable->select()
->setIntegrityCheck(false) // allows us to select from another table
->from($dbTable, array('titleGame'))
->where('idGameType IN (?)', $subselect);
$results = $select->query()->fetchAll(); // will throw an exception if the query fails
if(0 === count($results)) {
echo "No Results";
}else{
foreach($results as $result){
echo $result['titleGame'] . '<br />';
}
}
You can also write the SQL as a string, but when possible, the object-oriented approach is ideal because it makes the queries more portable, and most importantly makes it very easy to secure your queries.
Example:
$db = Zend_Db_Table::getDefaultAdapter(); // get the default Db connection
$db->select("select * from table where id = 3"); // doable, but not recommended
You can also create a prepared statement through Zend_Db_Statement to PHP's PDO extension.
$sql = 'SELECT * FROM bugs WHERE reported_by = ? AND bug_status = ?';
$stmt = new Zend_Db_Statement_Mysqli($db, $sql);
$stmt->execute(array('goofy', 'FIXED'));
The first approach, the object oriented fluent interface is what you will see the most, and the method I would recommend starting out with and using.
Read through the Zend_Db Manual Pages, and in particular, Zend_Db_Table_Select, Zend_Db_Table, and Zend_Db_Adapter for more information. Even a quick read through over the ZF Quickstart paying specific attention to the Db portion is helpful. It will show how to set up table classes to be a gateway between your application and the database.

Answer 2

SELECT titleGame FROM Game
LEFT JOIN GameType ON GameType.idGameType = Game.idGameType
WHERE GameType.nameGameType = 'Xbox'
Why not use a join instead? From my experience a subselect inside of IN is very slow in MySQL.
$select = $db->select();
$select->from('Game', array('titleGame'));
$select->joinLeft('GameType', 'GameType.idGameType = Game.idGameType', array());
$select->where("GameType.nameGameType = 'Xbox'");