Both are implementations of the Data Mapper template.
While phpDataMapper is a more loyal approach to the template, I found that it is sometimes too idealistic and strict.
OutletORM, on the other hand, is much more pragmatic and flexible (it does not require you to extend any base classes, for example). This is also a more mature project.
Doctrine is a great project, but huge and bloated for the simplest applications.
I would go with an Outlet!
Alex weber
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