Introduction to Data Management

ManualsBrandsHP ManualsServerHP NonStop G-Series

Accessing Databases With NonStop SQL

3-2 15873 Tandem Computers Incorporated

Figure 3-1. Tables in a NonStop SQL Database

S8020-007

EMPLOYEE Table

568

ROGER

JERRY

JESSICA

GREEN

HOWARD

CRINER

9000

1000

3500

100

300

175500.00

137000.00

39500.00

DEPT Table

DEPTNUM DEPTNAME MGR RPTDEPT LOCATION

1000

1500

9000

213

9000

1000

9000

CHICAGO

JOB Table

JOBCODE JOBDESC

100

250

900

MANAGER

ASSEMBLER

SECRETARY

FINANCE

PERSONNEL

CORPORATE

EMPNUM FNAME LNAME DEPTNUM JOBCODE SALARY

Although NonStop SQL stores your data only once so that it is easy to maintain, the

simple tabular database structure lets different users view the same data in many

different ways. For example, when accessing a table that contains employee data, you

can select only the rows that describe employees in Department 3500 or only the

columns that contain employee names and job codes. If two or more tables share a

column with the same type of data, you can simultaneously select data from both

tables.

You can select rows or columns, or both, from one or more tables to produce new

logical tables called views, as shown in Figure 3-2. You can name these views and

save them for future use.

At any time, you can add new tables, views, and columns, and change attributes of

objects in your database, all without affecting existing applications.