Take the pain out of dealing with relational databases in an object-oriented programming world. With this short book, you can save time and money by simply coding less while accomplishing more with the Doctrine persistence framework, a leading persistence solution for PHP programmers and web developers. PHP Persistence teaches you about PHP persistence and how to use it effectively for your database-driven applications. Bestselling author Michael Romer leverages his own vast experience to show you what you need to know about Doctrine 2 and how to use it in your own projects. Along the way you’ll learn about powerful persistence techniques, such as object-relational mapping (ORM) in PHP. What You'll Learn Define entities and references between entities Manage entities Master the Doctrine Query Language Use appropriate command-line tools for PHP persistence Program for caching  Who This Book Is For Experienced PHP programmers and web developers with some exposure to PHP.