This question is perhaps better suited for a specific MVC forum, but I hope I can get an answer here, since I learned MVC with the book: how do the levels of abstraction work in controllers?
For models it's simple: each table has its model file, with the functions you want to perform in it.
For views its equally simple: each page corresponds to a view file.
For controllers I don't see it so clearly. When should something be included as a function of the welcome (default) controller? When should it be placed in a separate controller? When should it be placed in a sub directory of the controller directory?
Is there a definite answer to these questions or is it more of a personal choice?
Thank you for the help!
William

It's a bit of a personal choice. For me, if I needed to do something repeatedly (say, for example, importing a CSV file) I would put that into a helper or library so I could use it from multiple controllers. If however, what I was facing was an organizational issue (say, an admin area of a website) I would use subfolders to keep things organized (instead of just putting all my functions into one controller).

Controllers are just a way to organize your code. They translate into routes. Once you get your head around that, you can pretty much do what feels best (of course, if you are handing your code off to someone else, you have to be merciful to them too!).

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