Beginning Microsoft SQL Server 2008 ... - S3 Tech Training

Chapter 10: Views
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columns to a group of people, but don’t want them to be able to see the general table structure or data?
One solution would be to keep a separate table that includes only the columns that we need:
Employees
EmployeeID
FirstName
MiddleInitial
LastName
Title
HireDate
TerminationDate
ManagerEmpID
Department
While on the surface this would meet our needs, it is extremely problematic:
❑ We use disk space twice.
❑ We have a synchronization problem if one table gets updated and the other doesn’t.
❑ We have double I/O operations (you have to read and write the data in two places instead of
one) whenever we need to insert, update, or delete rows.
Views provide an easy and relatively elegant solution to this problem. When we use a view, the data is
stored only once (in the underlying table or tables) — eliminating all of the problems just described.
Instead of building our completely separate table, we can just build a view that will function in a nearly
identical fashion.
To make sure we know the state of our Accounting database, let's create a special version of it for use in
the next example or two. To do this, load the CChapter10AccountingDBCreate.sql file (supplied
with the source code) into the Management Studio and run it. Then add the following view to the
AccountingChapter10 database:
USE AccountingChapter10;
GO
CREATE VIEW Employees_vw
AS
SELECT EmployeeID,
FirstName,
MiddleInitial,
LastName,
Title,