[DC-371] Lazy loading - doctrine makes extra queries into db

Thu, 23 Dec 2010 20:22:10 +0000

Just downloaded symfony 1.4

First of all I have a query:

$q = \Doctrine_Query::create()
->select('u., ur.')
->from('UserDb u')
->leftJoin('u.RealUserDetailsDb ur')
->leftJoin('u.MockUserDetailsDb um')
->where('u.id = :user_id')
;
$user = $q->fetchOne(array(':user_id' => $uid));

After that I'm accessing the fields of this object:

$userArray = array(
'id' => $this->getUser()->getId(),
'real_user_details_id' => $this->getUser()->getRealUserDetailsId(),
'mock_user_details_id' => $this->getUser()->getMockUserDetailsId(),
'real_user_details' => array(),
'mock_user_details' => array()
);

This is the actual queries into DB:

NR1:
SELECT u.id AS u_id, u.user_real_id AS uuser_real_id, u.user_mock_id AS uuser_mock_id, u2.id AS u2id, u2.nickname AS u2nickname, u2.email AS u2_email FROM user u LEFT JOIN user_real u2 ON u.user_real_id = u2.id LEFT JOIN user_mock u3 ON u.user_mock_id = u3.id WHERE (u.id = :user_id)

NR2:
SELECT u.id AS u_id, u.user_real_id AS uuser_real_id, u.user_mock_id AS u_user_mock_id FROM user u WHERE (u.id = '1') LIMIT 1

As you can see there are TWO queries however there should be only one query. The problem is that u.user_real_id is NULL in database and when I do 'real_user_details_id' => $this->getUser()->getRealUserDetailsId() doctrine does not have enough intelligence to understand that these fields have been already requested in NR1. If I comment this field, everything works well.

SURPRISE!
And now a surprise... if I modify a little bit my first query: "~~>select('u.')" instead of , "~~>select('u., ur.*')" it WON'T make TWO queries. It will make ONLY ONE!

As you understand this a very critical bug and of course our system won't go to production with this bug.

P.S. Is it possible to turn off the lazy loading in doctrine?

Doctrine Project

[DC-371] Lazy loading - doctrine makes extra queries into db