Agnostic OO PHP class to handle database?

h4x0rmx

I have been using PHP OO capabilities for a while now, but not to it's full extent for what I've been recently reading.

I was just reading about some advantages of having data as instances of a class instead of having (multidimensional) arrays.
The code shown talked about an agnostic class to interact with the database. This class would have a "persist" method. It would receive an instance of Person, for example, and store it in my MySQL db, or SQL, or even simple text or xml.
The book talked about the use of interceptors to implement the "delegate pattern", which makes really easy to change the implementation of your storage class.

Since I'm going to start working in a big project, I wanted to start right and I wanted to have something like this in my code, where everything is an object.
I didn't know how to search for something like this, but is there a good tutorial or an existing (sample) of a class that would allow me to interact with my database in an agnostic way, allowing me to change the implementation easily and treating everything as an object?
[I know I'll have to do some of the implementation to have everything work with my custom classes, but a tutorial or some well-documented sample code would be great]

I will really appreciate any help!

NogDog

Since no one else has replied, I'll chip in even though it's not an area of expertise for me. I'm guessing maybe you want to look at DAO (Data Access Objects)?

h4x0rmx

NogDog;10982207 wrote:
Since no one else has replied, I'll chip in even though it's not an area of expertise for me. I'm guessing maybe you want to look at DAO (Data Access Objects)?

I'll look into DAO, if anyone else has another idea/suggestion I'll appreciate it!

Thanks!

johanafm

Other things to search for are "database mapping", "object relational mapping" or "ORM". And I believe you should generally stick to inheritance over delegation. But you might also want to have a look at the strategy pattern.

sneakyimp

I've had some discussion about this type of thing here before. Here's my first attempt with some interesting responses from Jazz Snob.

More recently I referred someone else to the same article in their post and we ended up kicking around some ideas.

I also posted about an ORM system called Doctrine recently. It looks pretty damn ugly to me as one must learn YAML and its own god-awful syntax when trying to just write a simple join.

And finally, I posted more recently asking about Zend_DB which looks fairly interesting. In every case, the underlying DBMS or "persistence mechanism" you choose eventually rears its ugly head in the code you write. Consider reading this interesting article laserlight posted on the law of leaky abstraction.