Aaron Wormus and the Zend Developer Zone have posted the latest edition of their "Hidden Gems" series looking at the lesser-known features of the Zend Framework. This time, it's a look at Zend_Db (database abstraction).
Zend_Db is a layer which sits above the native PDO database extension. Before PDO (pre-PHP5.1) all we had to connect to databases were libraries that were developed in individual cycles and development teams, with little regard to what other database extensions were doing.
Taking this speed benefit of using PDO to do a majority of the work, PDO wrapper libraries like Zend_Db can supplement PDO with their own wrapper code leaving you with a fairly lightweight yet feature-rich database abstraction layer.
Aaron looks at connecting to a database (using both the PDO and DSN connections) and some example code showing how to work with the database using them - including queries and using transactions.