What's the point of a candidate key?

Question

I\'m fairly new to database management and this question never seems to be answered in more than one sentence. All other SO answers say \"A candidate key is a minimal super

Answer 1

It means that if PhoneNumber was indeed a candidate key you could delete the ID column and use PhoneNumber instead. In other words, it is a candidate for being a unique key.

Wikipedia has a more formal definition that you many want to look at.