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No non-prime attribute of R is transitively dependent on the primary key. A non-prime attribute of R is an attribute that does not belong to any candidate key of R. [3] A transitive dependency is a functional dependency in which X → Z (X determines Z) indirectly, by virtue of X → Y and Y → Z (where it is not the case that Y → X). [4]
The columns in a candidate key are called prime attributes, [3] and a column that does not occur in any candidate key is called a non-prime attribute. Every relation without NULL values will have at least one candidate key: Since there cannot be duplicate rows, the set of all columns is a superkey, and if that is not minimal, some subset of ...
A non-prime attribute of a relation is an attribute that is not a part of any candidate key of the relation. Put simply, a relation (or table) is in 2NF if: It is in 1NF and has a single attribute unique identifier (UID) (in which case every non key attribute is dependent on the entire UID), or
Every non-prime attribute has a full functional dependency on each candidate key (attributes depend on the whole of every key) [5] Every non-trivial functional dependency either begins with a superkey or ends with a prime attribute (attributes depend only on candidate keys) [5]
In the Today's court bookings table, there are no non-prime attributes: that is, all attributes belong to some candidate key. Therefore, the table adheres to both 2NF and 3NF. The table does not adhere to BCNF. This is because of the dependency Rate type → Court in which the determining attribute is Rate type, on which Court depends.
A table (called the referencing table) can refer to a column (or a group of columns) in another table (the referenced table) by using a foreign key.The referenced column(s) in the referenced table must be under a unique constraint, such as a primary key.
Attribute-based access control (ABAC), also known as policy-based access control for IAM, defines an access control paradigm whereby a subject's authorization to perform a set of operations is determined by evaluating attributes associated with the subject, object, requested operations, and, in some cases, environment attributes.
Normalization (to first normal form) is a process where attributes with non-simple domains are extracted to separate stand-alone relations. The extracted relations are amended with foreign keys referring to the primary key of the relation which contained it. The process can be applied recursively to non-simple domains nested in multiple levels. [4]