Building a View

Abstract

A view is a virtual table that, in itself, doesn’t contain any data or information. All it contains is the query that the user defines when creating the view. A view is actually a named query against one or more tables. Views are used as a security measure (to restrict users to specific columns or rows), as a method of joining data from multiple tables (and presenting it as if it resides in one table), and by returning summary data instead of detailed data. Another use for a view is to provide a method of accessing the underlying data in a manner that provides the end user with a business layout. For example, you will see within this chapter a view that shows customer details along with enriched transaction details, thus making it easier for anyone interrogating your data, even someone who has no knowledge of the underlying data model, to access useful information.