DQL (Doctrine Query Language) is a object query language which allows you to find objects. DQL understands things like object relationships, polymorphism and inheritance (including column aggregation inheritance). For more info about DQL see the actual DQL chapter.

Doctrine_Query along with Doctrine_Expression provide an easy-to-use wrapper for writing DQL queries. Creating a new query object can be done by either using the new operator or by calling create method. The create method exists for allowing easy method call chaining.