Relational Integrity

The relational database schema for The Suppliers and Parts database is shown below: S    (Sno, Sname, Status City) P    (Pno, Pname, Color, Weight, City) SP   (Sno, Pno, Qty) A superkey is an attribute (or set of attributes) that uniquely identifies a tuple in a relation For example the combination Sno,Sname uniquely identifies a tuple in S. A candidate

Relation Model

Relation – A table with columns and rows. Attribute – A named column of a relation. Domain – The set of allowable values for one or more attributes. Tuple – A row of a relation. Intension – The structure of a relation (i.e. its attributes), together with a specification of the domains and any other restrictions on possible values. The structure