Reading Time: 1 minute The relational algebra consists of: a set of eight operators (which ones?) and a relational assignment operation The relational assignment operation allows us to assign a name to the result of a relational expression, for example if we take the product of two relations A and B, then: C ← A X B shows that

Relational Integrity

Reading Time: 2 minutes 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

Reading Time: 1 minute 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