Also on the space matter i'm not concern about size, only was concern about database integrity...
Yes, this is why I made the alternate suggestion. The most significant integrity issues arise because you're using multiple movie records to record different media versions. That means all the information that is supposed to be the same (e.g., most of the data that comes from IMDb) has to be kept in sync. With respect to that information, each of these movie records is a duplicate—which raises a whose set of other integrity issues (e.g., which movie records get updated when you download a person's filmography?). Ironically, posters are one of number of data elements that could be associated with either the movie (e.g., an official poster created by the producer for the initial promotion of the movie) or the media (e.g., the cover of a specific DVD release).
Just to illustrate the point... If your "thing" was to collect multiple versions of movies (and no series), then the best available solution would be to record multiple movie versions as series. All the information about the movie itself would be recorded in the main record. Any and all information unique to a particular version would be recorded in an episode record. Both record types could include appropriate posters. Information in the main movie records would be updated "normally"—without any integrity issues. Any information that comes from the media itself (e.g., media info scanned from the file(s), screenshots) would automatically go to the appropriate episode record. Although there are currently no plugins for downloading version-specific information (i.e., DVD editions), using a separate episode record makes a complete set of fields available to record whatever unique information is necessary. For example, a description of exactly what has been added to an extended version could be recorded in
Description. A description or list of "additional features" on a DVD could be recorded in
Comments.
It would probably be fairly easy to modify the program so it could handle multiple versions in this way. The main (only?) impediment now is that doing so messes up series. The is only so because a movie record with episodes attached to it is assumed to be a series. All that's required is the use of a record type field to distinguish movies from series. This record type could default to "series" when episodes are added (as it does now), but could be changed back to "movie." For such records, seasons would be suppressed (this can be done now for series with only one season), and it would be evident the child records are versions, not episodes.