Introduction to Data Management

An Overview of Data Management
1-6 15873 Tandem Computers Incorporated
With a relational database, relationships between records (rows) are based on
common field values, and aggregate operators direct the system to the desired rows or
columns of the table. An application can, for example, request a display showing all
salespeople (in the employee table) who have placed orders (in the invoice table) for a
part (in the part table). By placing fewer restrictions on the structure and types of
queries that can be issued against it, a relational database allows applications greater
flexibility than do other forms of database.
The Tandem NonStop
Computer Systems
To help users meet their online transaction processing demands, Tandem offers its
NonStop computer systems. Each of these systems provides all of the vital
technological features described in this section:
An online multiprogramming operating environment
Convenient expandability that allows customers to extend a single system into a
larger configuration, and even into a vast network of many systems
Software that supports screen-oriented I/O processing for many different kinds of
terminals and workstations
A relational database management system, accompanied by software that simplifies
application program development and that maintains a consistent database
concurrently accessible by many users
In addition to these features, the Tandem systems also provide two other powerful
advantages:
NonStop transaction processing, where processing continues even when a
component fails, while equipment is being repaired or replaced, or while new
processors or peripheral devices are being added to the system
Independent multiprocessing, with many processors running simultaneously but
independently
More information about how the Tandem systems support the functions of data
management and online transaction processing appears in the following sections.