Question

I’m trying to use DQL to create a query between a ManyToMany relation, here a snippet of my code:

$em = $this->getDoctrine()->getEntityManager();
$query = $em->createQuery("SELECT * FROM TestGroupBundle:Question");

It’s a really basic SQL line, but I always get this weird error:

[Syntax Error] line 0, col 7: Error: Expected IdentificationVariable | StateFieldPathExpression | AggregateExpression | "(" Subselect ")" | ScalarExpression, got '*'

500 Internal Server Error – QueryException

Can someone tell me what does it mean please and how to fix it ? Thanks

Answer 1

You’re mixing up SQL and DQL. There’s no “*” in DQL since you’re working with your object model. The proper syntax would be "SELECT q FROM TestGroupBundle:Question q". The result is wrapped in \Doctrine\Common\Collections\ArrayCollection object. You can iterate over the object to get your results.

There’s one important thing to keep in mind about DQL:

A common mistake for beginners is to mistake DQL for being just some form of SQL and therefore trying to use table names and column names or join arbitrary tables together in a query. You need to think about DQL as a query language for your object model, not for your relational schema.