July 2002
Beginner
424 pages
9h 30m
English
Content preview from SQL: Visual QuickStart Guide
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Chapter 12. Views
A view is a stored SELECT statement that returns a table whose data is derived from one or more other tables (called underlying tables). Some important characteristics of a view are:
A view’s underlying tables can be base tables, temporary tables, or other views.
A view is called a virtual or derived table to distinguish it from a base or temporary table.
The DBMS stores a view as only a SELECT statement, not as a set of data values, thus preventing data redundancy.
A view materializes dynamically as a physical table when referenced by name in an SQL statement. It exists only for the duration of the statement and vanishes when the statement ends.
A view consists of a set of named columns and rows of data, so you can use it almost ...
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