Unit 3 The Relational Model And From ER Diagram To Relational Database

◆ In this unit, we learn the semantics of specifying a relational database, later we will learn the syntax of SQL for doing this ◆ The basic “datatype”, or “variable ” of a relational database is a relation ◆ In this unit, such a variable will be a set ◆ Later, we will extend this, and such a variable will be a multiset ◆ In SQL, such a variable is called a table ◆ We may use the term table for a relation in this unit too ◆ Good review of basic concepts and terminology is available a