In this chapter, the rest of the PostgreSQL building blocks, including views, indexes, functions, triggers, and rules, will be introduced. In addition to that, the web car portal schema will be revised. Several DDL commands, such as
ALTER, will also be introduced.
Since the lexical structure and several DML commands have not been introduced as yet, we will try to use very simple DML commands.
A view can be seen as a named query, or as a wrapper around a
SELECT statement. Views are essential building blocks of relational databases from the UML modeling perspective; a view can be thought of as a method for a
UML class. Views share several advantages over procedures, so the following benefits ...