Summary
In this chapter, we have learned about DQL, its differences from SQL, and its Query Builder. We also learned about the concept of entity repositories and how to create custom ones.
Even if there is a lot more to learn from these topics and from Doctrine in general, our knowledge should be sufficient to start developing complete and complex applications using Doctrine as a persistent system.
In Chapter 5, Going Further, the last chapter of this book, we will go a step further and cover some more advanced topics, including how to handle inheritance, how to make native SQL queries, and the basics of the event system.
