CIS 3530 Lecture Notes - Lecture 8: Relational Calculus, Tuple, Unique Key

• School: University of Guelph
• Department: Computing and Information Science
• Course: CIS 3530
• Professor: Fangjyu Wang

Document Summary

Account ( vno, vname, account(v t)) ( account(province = ont"(c)) Each entity type is transformed into a relation that includes ask the attributes of the entity set. The primary key of the entity type becomes the primary key of the corresponding relation. Each monkey attribute of the entity type becomes a monkey attribute of the relation. A binary 1:n relationship type can be represented by adding the primary key of the entity type on the one-side relationship type, as a foreign key in the relation that corresponds to the entity type on the many side. The other relational language we will learn, unlike relational algebra (which is procedural) relational calc is non procedural (aka declarative) A relational calculus expression is a normal de nition of the output relation in terms of input relations. There are 2 types of relational calculus, tuple calc and domain calc.