For example,

  • MOVIES (movieid, movietitle)

where movietitle can be any number of words, so I believe it's not atomic.

How do you bring something like that to 1NF?

  • What's the specific domain of movietitle? What are the constraints that apply to that domain? Do you have a real-world and representative set of sample values of that domain? Also, the post so far lacks any description of the business environment of relevance, so please address that issue. – MDCCL Oct 2 at 21:21
  • As it stands, an answer like this suffices. – MDCCL Oct 2 at 21:22
  • A movie title, regardless of how many words (or characters) are in it, is an atomic value. – mustaccio Oct 2 at 21:31
  • The comment above is correct as long as a given movietitle occurrence corresponds to exactly one value of the respective simple domain, but we don't know what the domain is in this very particular case; therefore, for the time being, it's impossible to determine with the precision demanded in professional database design all the aspects around first normal form in the scenario at hand. – MDCCL Oct 2 at 21:39

Atomic in this sense is a logical concept. Would you consider the integer 123 not atomic because it has more than one digit? 123 is an agreed upon singular fact, representing a point on the numbers axis. A movie title is the same - it represents a singular agreed upon fact, that a movie with that title exists in the real world. A non atomic value would be “rocky, rocky 2” - a value that specifies 2 facts , and that would violate 1NF. Same would go for the integer 123, if each digit represents a different fact. For example if 1 represents an item color code and the 23 its size.


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