what is doctrine hydration?
Doctrine has a concept of data hydrators for transforming your :php:class:`Doctrine_Query` instances to a set of PHP data for the user to take advantage of. The most obvious way to hydrate the data is to put it into your object graph and return models/class instances. Sometimes though you want to hydrate the data to an array, use no hydration or return a single scalar value. This chapter aims to document and demonstrate the different hydration types and even how to write your own new hydration types.