Why Use Views?

Inline views and database views are the only devices that enable some queries to retrieve the proper results. The next several paragraphs describe a typical situation in which a view is the best tool to provide the desired results.

Databases contain many paths through the data. It is very common for multiple branches to exist. Figure 10.1 illustrates this concept. Parent table Employee has two child tables: Glasses and Emp_tools. This results in two different branches beneath the Employee table.

Figure 10.1. Table relationship drawing depicting different branches

It is possible to join Employee to Glasses and Employee to Emp_tools. ...

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