Attribute Y is functionally dependent on attribute X if the value of attribute X determines the value of Y.
The functional dependency noted as A B, means that the value of A can be determined from the value of B.
A constraint that requires an instance of an entity to exist in one relation before it can be referenced in another relation is called an insertion anomaly.
If a table meets the minimum definition of a relation, it has an effective or appropriate structure.
Undesirable consequences of changing the data in a relation are called "modification anomalies."
A deletion anomaly exists when deleting data about one entity results in the loss of data about another entity.
Relations are classified into "normal forms" based on the types of modification anomalies that they are vulnerable to.
The essence of normalization is taking a relation that is not in BCNF and breaking it into multiple relations such that each one is in BCNF.
Breaking a relation into two relations may create the need for a referential integrity constraint to be defined between the two relations.
The multivalued dependency noted as A --> -->B, means that the value of A determines a set of values of B.
A(n) __________ is a relationship between attributes such that if we know the value of one attribute, we can determine the value of the other attribute.
If by knowing the value of A, we can find the value of B, then we would say thatB is ________ on A.
In functional dependencies, the attribute whose value is known or given is referred to as the ________ .
Given the functional dependency (A, B) --> C, the attributes (A, B) are referred to as a ____________.
A --> B, A --> C
Given the functional dependency A --> (B, C), then it is true that _______ and___________ .
A -->C, B --> C
Given the functional dependency (A, B) --> C, then it is not true that _______ and ________ .
A(n) _______ is a combination of one or more columns that is used to identify particular rows in a relation.
A(n) _____________is one of a group of keys that may serve as the primary key in a relation.
A(n) _______ is a candidate key that has been selected to uniquely identify rows in a relation.
A(n) ___________ is an artificial column that is added to a relation to be its primary key.
A(n) ___________ is one or more columns in one relation that also are the primary key in another table.
referential integrity constraint
A(n) ___________________ is used to make sure the values of a foreign key match a valid value of a primary key.
For some relations, changing the data can have undesirable consequences called __________________.
Relations are categorized into ____________ where the categorization is based on the problems the relation has.
A defining requirement for _____________ normal form is that every determinant must be a candidate key.
Domain/key normal form requires that every __________ be a logical consequence of the definition of domains and keys.
Every time we break up a relation during the normalization process, we may have to create ___________ constraints.