RedBeanPHP - Easiest ORM layer for php
RedBeanPHP is an open source ORM (object relational mapping) tool for PHP. It focuses on simplicity and ease of use. What makes RedBean unique is that it creates your database schema on-the-fly. It scans your data and adjusts the column types to fit your object properties. If your models are stabilized you can freeze the database. This way RedBean is easy to develop with but is also extremely fast on production servers.
RedBean requires zero configuration. No INI, YAML, XML or other config files. Just include the file in your code and you are done.
RedBean works with beans. Beans are simple objects that only have public properties. The idea behind RedBean is simple, you fill the bean with the properties you need and then you give it to RedBean and it will be stored in the database. No matter what. RedBean creates tables, columns and column types on the fly. No need to switch back-and-forth to phpmyadmin anymore! Just write your code and RedBean takes care of the database.
RedBeanPHP is compatible with the best open source databases around; MySQL, SQLite and PostgreSQL.