Why users have to implement general methods?

[Blangero Wang <bl...@gmail.com>]

Hello,

I've got some experience consuming odata and now I'm trying to implement my
odata v4 service, from my understanding in most cases the only difference
between different odata services should be 1.edmProvider and 2.data
storage/source.

But after checking the tutorials I find that some general methods, like
read entity/function import collection, apply filter/top/order, etc, need
to be implemented by users.

So my question is:
Why the general methods are expected to be implemented by users, does each
user usually have special requirements? If not, can I just treat the code
from tutorial as skeleton code?

Thanks and regards,
Blangero