BUSI 3400 Lecture Notes - Lecture 3: Superkey, Candidate Key, Referential Integrity
30 Dec 2016
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Document Summary
Relational database model (based on logical construct called a relation) enables logical representation of the data and its relationships. Attribute domain specific range of values for attributes. Keys help data integrity. ensure table row is uniquely identifiable, establish relationships among tables and to. Determination state in which knowing the value of one attribute makes it possible to determine the value of another. Functional dependence value of one or more attributes determines the value of one or more other attributes. Attribute whose value is determined by the other attribute. Full functional dependence minimum number of attributes is used as the determinant. Composite key key that is composed of more than one attribute. Key attribute attribute that is a part of a key. Entity integrity condition in which each row in the table has its own unique identity (pk is unique and not null) Absence of any data value that could represent an unknown attribute value, known but.
