Say I have a property listings table and a listings_categories table which determines if the listing is for sale, rent and/or season rent. Depending which categories a listing has (min of 1 required), a price value or timespan (in case of season rent) may be required.
How should I deal with these price fields? Should they be placed in the listings, or move them to the listings_categories table? These price fields are somewhat essential to the app and will always be displayed — would I have any problems appending them to the rest of the main listing table?
I would say if listings_categories only has one column and 3 possible fields, you ought to just store all of that in the listings table. No reason to join when you don’t have to.