DDC-1001: Join statement fails

[doctrinebot]

Jira issue originally created by user rrafal@gmail.com:

I tried to execute this DQL statement:

SELECT u FROM RoomMember m JOIN m.user u WHERE m.room = :roomId

It failed with this error:

class_parents(): object or string expected

Doctrine/ORM/Mapping/ClassMetadataFactory.php:222
Doctrine/ORM/Mapping/ClassMetadataFactory.php:245
Doctrine/ORM/Mapping/ClassMetadataFactory.php:169
Doctrine/ORM/EntityManager.php:247
Doctrine/ORM/Internal/Hydration/ObjectHydrator.php:223
Doctrine/ORM/Internal/Hydration/ObjectHydrator.php:76
Doctrine/ORM/Internal/Hydration/AbstractHydrator.php:98
Doctrine/ORM/AbstractQuery.php:527

I rewrite the query like this, and it works:

SELECT u FROM RoomMember m , User u WHERE m.user = u AND m.room = :roomId

Let me know if you need more information.
Rafal - rrafal@gmail.com

[doctrinebot]

Comment created by @beberlei:

It seems either your mapping files are wrong, can you post the mappings of RoomMember?

[doctrinebot]

Comment created by rrafal@gmail.com:

I simplified my code to the following and run the test again:

/****

• @entity

• @table(name="user")
  /
  class User
  {
  /***

  • @id
  • @GeneratedValue
  • @column(name="user_id", type="integer")
    */
    private $id;

  public function **construct() { }
  public function getId(){ return $this->id; }
  }

/****

• @entity

• @table(name="room_member")
  /
  class RoomMember {
  /***

  • @id
  • @GeneratedValue
  • @column(name="room_member_id", type="integer")
    */
    private $id;

  /****

  • @manytoone(targetEntity="User")
  • @joincolumn(name="user_id", referencedColumnName="user_id")
    */
    private $user;

  public function **construct(User $user){
  $this->user = $user;
  }

  /****

  • User who belongs to room.
  • @return User
    */
    public function getUser(){
    return $this->user;
    }
    }

$query = $this->em->createQuery('SELECT u FROM RoomMember m , User u WHERE m.user = u');
$query->execute();// No problem

$query = $this->em->createQuery('SELECT u FROM RoomMember m JOIN m.user u');
$query->execute();// Error

I also tried to recreated this problem using the repository version of doctrine. I created same entities in sandbox environment (doctrine2-orm/tools/sandbox). I'm getting a different error message:

PHP Fatal error: Uncaught exception 'Doctrine\ORM\Query\QueryException' with message '[Semantical Error] line 0, col -1 near 'SELECT u FROM': Error: Cannot select entity through identification variables without choosing at least one root entity alias.' in doctrine2-orm/lib/Doctrine/ORM/Query/QueryException.php:47
Stack trace:
#0 doctrine2-orm/lib/Doctrine/ORM/Query/Parser.php(425): Doctrine\ORM\Query\QueryException::semanticalError('line 0, col -1 ...')
#1 doctrine2-orm/lib/Doctrine/ORM/Query/Parser.php(335): Doctrine\ORM\Query\Parser->semanticalError('Cannot select e...')
#2 doctrine2-orm/lib/Doctrine/ORM/Query/Parser.php(281): Doctrine\ORM\Query\Parser->assertSelectEntityRootAliasRequirement()
#3 doctrine2-orm/lib/Doctrine/ORM/Query.php(203): Doctrine\ORM\Query\Parser->parse()
#4 doctrine2-orm/lib/Doctrine/ORM/Query.php(223): Doctrine\ORM\Query->_parse()
#5 /home/rrafal/Develo in doctrine2-orm/lib/Doctrine/ORM/Query/QueryException.php on line 47

I'll attache my code from sandbox.
Thank you for help.

[doctrinebot]

Comment created by @beberlei:

Ah yes, the query you want to do is not possible. I have only seen that now. You have to select the "m" if you have RoomMember in the FROM clause. That is what the exception in the sandbox is about. Are you using an older version of Doctrine (RC1 or less) for your project? The exception is realtively new

[doctrinebot]

Issue was closed with resolution "Invalid"

[doctrinebot]

Comment created by rrafal@gmail.com:

Ok, thanks for the explanation. I'll just used the alternative DQL, it works perfectly:
SELECT u FROM RoomMember m , User u WHERE m.user = u

I'm using doctrine ORM 2.0.0