I think the minimum that should be provided are the small number of fields for information unique to each season—poster, synopsis, comments and (maybe) rating. All these would be entered manually and would not be searchable, sortable or groupable. If anything beyond that is to be considered, it should probably be calculated fields. Some might simply be equal to a corresponding series field (e.g.,
Genre), some would be the range that exists in the episodes (e.g.,
Release date and
Year), an average (e.g., rating) or an aggregation (e.g., credits). These have the advantages of not requiring any maintenance, being informative in their own right, and not making the database more complicated by introducing more relations.
Actually, I thought of smth like "combined details" on IMDB with a possibility to edit fields settings the values for all episodes in a season, so there will be no need to add an extra record to the database.
This sounds very much like the second part of my suggestion, although I'm not sure what you mean by "with a possibility to edit fields settings..." And I think the first part is important—at least the ability to add a poster and some kind of unique description.
