Prevent fetching column when it is marked as `#[sea-orm(skip)]`

[anshap1719]

Motivation

This relates to #1954. I always assumed (and that's my bad) that marking a column as skip would not only use a default value for it (this works), but also not fetch it from the DB since the value is fetched and then thrown away (this doesn't work).

Since the original implementation had no mention of the latter, I am wondering if this is an intentional design choice. If yes, I'd like to know if you'd prefer a different attribute for skipping column fetch from DB.

Proposed Solutions

The current implementation dictates that all fields in the generated Column enum are selected by default when fetching data from DB.

In an ideal situation, the skipped columns shouldn't be fetched. It remains to be seen if they should be skipped unconditionally, or only by default–meaning they will be fetched if manually requested.

If we're not skipping the fetching of data part, then I'm not sure why the skip attribute exists at all. It sounds very misleading, but that's just a personal experience.

Additional Information

I'd be happy to create a PR for whichever way we decide to go with.

[Huliiiiii]

I think it's better to skip column fetch. What do you think? @tyt2y3