Propel - smart easy object persistance in PHP
Propel is an open-source Object-Relational Mapping (ORM) for PHP5. It allows you to access your database using a set of objects, providing a simple API for storing and retrieving data. Propel uses PDO as an abstraction layer, and code generation to remove the burden of runtime introspection. Therefore Propel is fast.
Propel implements all the key concepts of mature ORM layers: the ActiveRecord pattern, validators, behaviors, table inheritance, reverse engineering an existing database, nested sets, nested transactions, lazy loading, LOB, etc. Propel supports MySQL, PostgreSQL, SQLite, MSSQL, and Oracle.