When is it better to store flags as a bitmask rather than using an associative table?

Question

I’m working on an application where users have different permissions to use different features (e.g. Read, Create, Download, Print, Approve, etc.). The list of permissions i

Answer 1

The only time I can think of when I would use a bitmask field to store permissions, is when you are really really constrained in how much physical memory you have....like maybe on an old mobile device. In truth, the amount of memory you save isn't worth it. Even at millions of users hard drive space is cheap, and you can expand permissions etc. a lot easier by using the non-bitmask approach (this about reporting off of who has what permissions etc.)

One of this biggest headaches I've run into with it is assigning users permissions directly in the database. I know you should try and use the application to administer itself and not-much with application data in general, but sometimes, it's just necessary. Unless the bitmask is actually a character field, and you can easily see what permissions someone has instead of an integer, try explaining to an analyst etc. how to give write access etc. to someone by updating the field.....and pray your arithmetic is correct.