Fifth normal form (5NF), also known as project-join normal form (PJ/NF) is a level of database normalization designed to reduce redundancy in relational databases recording multi-valued facts by isolating semantically related multiple relationships. A table is said to be in the 5NF if and only if every join dependency in it is implied by the candidate keys.
A join dependency *{A, B, … Z} on R is implied by the candidate key(s) of R if and only if each of A, B, …, Z is a superkey for R.
Read more about Fifth Normal Form: Example
Famous quotes containing the words normal and/or form:
“You have promise, Mlle. Dubois, but you must choose between an operatic career and what is usually called “a normal life.” Though why it is so called is beyond me.”
—Eric Taylor, Leroux, and Arthur Lubin. M. Villeneuve (Frank Puglia)
“The literary critic, or the critic of any other specific form of artistic expression, may detach himself from the world for as long as the work of art he is contemplating appears to do the same.”
—Clive James (b. 1939)