I need to draw an ERD of a online music database. Each album could have at most three formats (mp3, vinyl, cd) and two status (used or not). I am thinking about creating an entity called "album" containing title，format，etc. as my attributes, different formats have a different UID. The thing is I couldnot decide how to deal with "used" attribute, because the price of an album could be different depending on the boolean value. Can I just have another entity containing "price" as attribute, and use "used" as the attribute of the relationship between two entities?
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Possible duplicate of [How can you represent inheritance in a database?](https://stackoverflow.com/questions/3579079/how-can-you-represent-inheritance-in-a-database) – philipxy Oct 09 '18 at 04:56
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Hi. This is a faq. Please always google many clear, concise & specific versions/phrasings of your question/problem/goal with & without your particular strings/names & read many answers. Add relevant keywords you discover to your searches. If you don't find an answer then post, using 1 variant search as title & keywords for tags. See the downvote arrow mouseover text. When you do have a non-duplicate code question to post please read & act on [mcve]. – philipxy Oct 09 '18 at 04:57