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  • Thank you for your answer. So if in the future I need to add a few more columns to extend functionality, it would still be better then EAV? For instance, if a table has 1 million records, adding 5 optional fields to the events table will add 5 million empty fields to the database. Using EAV would add 0 empty fields. This is the only concern I have. Do you think even in this situation it would still be better to add columns to the appropriate table then to just add a event_meta table? Commented Aug 6, 2014 at 15:58
  • @alwaysStuck If you want to use relational databases, you should adhere to normal forms. If you want to use no-sql databases, that are key-value-based, non relational type of databases, you can do as you are proposing here. Also a great number of optional fields in an entity is a bad design, indicating an extra entity is needed. For example a doctor-guild-number in the person table will be empty for almost everyone, a doctor-table with a one-one relationship with person should hold all attributes only applicable to doctors. Commented Aug 6, 2014 at 16:07
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    @alwaysStuck: There's nothing wrong with using a SQL database table as a Key/Value store or EAV, if Key/Value or EAV are the right tools for the task. Commented Aug 6, 2014 at 16:44
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    @alwaysStuck -- one thing we've used successfully for things like this would be to have an extra metadata field that is just a serialized object. The key caveat there is it works great if you never, ever need to query on the contents. Commented Aug 6, 2014 at 16:54
  • @alwaysStuck: existing table rows are not modified when a new column is added to the table. Commented Aug 6, 2014 at 16:59