CREATING AN ABSTRACTION LAYER IN SQL SERVER - A Developer's Guide to Data Modeling for SQL Server - page 247

Table 11.1 Properties of the Order Object and the Related Attribute
from the Orders Entity

Property Attribute

Order_Number OrderNumber

Date OrderDate

SubTot SubTotal

SH ShippingHandling

Tax Tax

Order Total Total

Address 1 AddressLine1

Address 2 AddressLine2

City City

State Region

Country Country

Zip ZipCode

Split IsSplitShip

EmployeeID EmployeeObjectID

CustomerID CustomerObjectID

Shipping_Method ShippingMethodsObjectID

also apply to canceling an order; a stored procedure gets called, and it
changes the order's status and maybe triggers a customer refund.
The possibilities are endless, and when you are building your database,
you should take them into account. If your database is tightly integrated
with an application development project, you may find that an object
model exists. We recommend that you use this model as a guide to help
you build your abstraction layer. After all, the application will ultimately
use the database directly, so the two should be tightly coupled.

Implementing an Abstraction Layer

Implementing an abstraction layer consists of creating objects in the data-
base that act as intermediaries between application code and underlying
core database objects. You can use views, stored procedures, and functions
to create easily accessible entry points for applications to use.