DQL语句汇总

DQL as a query language has SELECT, UPDATE and DELETE constructs that map to their corresponding SQL statement types. INSERT statements are not allowed in DQL, because entities and their relations have to be introduced into the persistence context through EntityManager#persist() to ensure consistency of your object mode.

DQL SELECT statements are a very powerful way of retrieving parts of your domain model that are not accessible via associations. Additionally they allow you to retrieve entities and their associations in one single SQL select statement which can make a huge difference in performance compared to using several queries.

DQL UPDATE and DELETE statements offer a way to execute bulk changes on the entities of your domain model. This is often necessary when you cannot load all the affected entities of a bulk update into memory.

1. bulk insert

setStatus('user');
    $user->setUsername('user' . $i);
    $user->setName('Mr.Smith-' . $i);
    $em->persist($user);
    if (($i % $batchSize) === 0) {
        $em->flush();
        $em->clear(); // Detaches all objects from Doctrine!
    }
}
$em->flush(); //Persist objects that did not make up an entire batch
$em->clear();

2.update

$q = $em->createQuery('update MyProject\Model\Manager m set m.salary = m.salary * 0.9');
$numUpdated = $q->execute();

3.delete

$q = $em->createQuery('delete from MyProject\Model\Manager m where m.salary > 100000');
$numDeleted = $q->execute();

4.select

$query = $em->createQuery('SELECT u FROM MyProject\Model\User u WHERE u.age > 20');
$users = $query->getResult();

5.join

$query = $em->createQuery('SELECT p.dlrId,a.sqrId FROM AppBundle:Agent p JOIN AppBundle:Applicant a where p.dlrId=:dlrid')
->setParameter('dlrid',13);
$users = $query->getResult();

left join

$query = $em->createQuery('SELECT u.id, a.id as article_id FROM CmsUser u LEFT JOIN u.articles a');
$results = $query->getResult();

Restricting a JOIN clause by additional conditions specified by WITH

$query = $em->createQuery("SELECT u FROM CmsUser u LEFT JOIN u.articles a WITH a.topic LIKE :foo");
$query->setParameter('foo', '%foo%');
$users = $query->getResult();

Using several Fetch JOINs

$query = $em->createQuery('SELECT u, a, p, c FROM CmsUser u JOIN u.articles a JOIN u.phonenumbers p JOIN a.comments c');
$users = $query->getResult();

6.count

$dql = "SELECT count(a.id) as total FROM AppBundle:Applicant a ";
$query = $em->createQuery($dql);
$all = $query->execute(); //[{"total":"11"}]

$dql = "SELECT count(a.id) as total FROM AppBundle:Applicant a ";
$query = $em->createQuery($dql);
$all = $query->getSingleScalarResult();//"11"

7.With WHERE Clause and Positional Parameter

$query = $em->createQuery('SELECT u FROM ForumUser u WHERE u.id = ?1');
$query->setParameter(1, 321);
$users = $query->getResult();

With WHERE Clause and Named Parameter

$query = $em->createQuery('SELECT u FROM ForumUser u WHERE u.username = :name');
$query->setParameter('name', 'Bob');
$users = $query->getResult();

8.With Nested Conditions in WHERE Clause

$query = $em->createQuery('SELECT u FROM ForumUser u WHERE (u.username = :name OR u.username = :name2) AND u.id = :id');
$query->setParameters(array(
    'name' => 'Bob',
    'name2' => 'Alice',
    'id' => 321,
));
$users = $query->getResult();

9.Retrieve user entities with Arithmetic Expression in ORDER clause

$query = $em->createQuery('SELECT u, u.posts_count + u.likes_count AS HIDDEN score FROM CmsUser u ORDER BY score');
$users = $query->getResult(); // array of User objects

10.EXISTS in WHERE clause with correlated Subquery

$query = $em->createQuery('SELECT u.id FROM CmsUser u WHERE EXISTS (SELECT p.phonenumber FROM CmsPhonenumber p WHERE p.user = u.id)');
$ids = $query->getResult();

11.Get all users that have more than 1 phonenumber

$query = $em->createQuery('SELECT u FROM CmsUser u WHERE SIZE(u.phonenumbers) > 1');
$users = $query->getResult();

12.Get all users that have no phonenumber

$query = $em->createQuery('SELECT u FROM CmsUser u WHERE u.phonenumbers IS EMPTY');
$users = $query->getResult();

摘抄链接 https://www.doctrine-project.org/projects/doctrine-orm/en/2.6/reference/dql-doctrine-query-language.html#doctrine-query-language