X-Combinator

MySQL 5.0 supports a great new feature called views. Here’s a quick summary of what views are.

Views are also sometimes known as virtual tables, because they’re defined in terms of (other) tables through the use of queries…
However, a view is not merely a convenient container for a subset of records from a table. For one thing, a view is a “live” or dynamic snapshot of table data; when the data in the underlying table changes, so does that in the view.
-Devshed

As you can imagine, views can be very handy when doing database analysis.

Read more:

• MySQL Docs on Views
• Views in Rails