When you start working with data in an application, you may need to use an object-relational mapper (ORM), a layer between the database and application. For PHP the two most frequently used ORM’s are Doctrine and Propel. That’s why I decided to compare the main features of Doctrine in version 2.4.7 and Propel in version 2.0. At this point, I must strongly emphasize that this article is not to indi