Pathmaker Programming Guide

Defining Data for a Pathmaker Project

Preparing for Pathmaker Application Development

2–28 067868 Tandem Computers Incorporated

Creating Constraints

You can create constraints for a table definition to control the values allowed for a

column. Creating simple constraints on a column allows the Pathmaker product to

generate MUST BE checks in the requester. Note that the Pathmaker product cannot

generate MUST BE checks for every type of constraint that you can create in SQL.

Table 2-3 lists some examples of SQL expressions that can be used in a constraint

statement and indicates whether Pathmaker can translate the expression into a MUST

BE check.

Table 2-3. SQL Constraints and Pathmaker MUST BE Checks

Expression Translated Into MUST BE?

QTY_ORDERED BETWEEN 400 AND 500

STATE IN (“CALIFORNIA”, “ARIZONA”)

QTY_ORDERED < 500

Yes

COLUMN1 > COLUMN2

CUSTNAME LIKE “MART%”

NonStop SQL Data Definition Features Related to Pathmaker Programming

The language used to define data for NonStop SQL has three features that are related

to Pathmaker programming. Two NonStop SQL DDL clauses, HEADING and

UPSHIFT, can be used in any NonStop SQL data definition statement that adds or

alters columns, such as CREATE TABLE, CREATE VIEW, or ALTER TABLE. The

HELP TEXT statement can be used to specify or delete help text for a NonStop SQL

object. Table 2-4 briefly describes these three NonStop SQL DDL features.

Table 2-4. Related NonStop SQL Data Definition Language Features

Feature Description

HEADING clause Allows you to specify default prompt text for a data field. If you do not use

HEADING or if you use the NO HEADING clause, the default prompt text

is the column name.

UPSHIFT clause Causes the application to change all lowercase alphabetic characters into

uppercase alphabetic characters before they are entered into the

database. UPSHIFT helps ensure the consistency of your database.

You should use UPSHIFT on any character field that acts as a primary or

foreign key.

HELP TEXT statement Allows you to specify help text for a column, constraint, index, table, or

view.

You can alter heading text and help text or enter text for the first time by using the

Display Detail screen in Pathmaker. The Display Detail screen also allows you to add

information that you cannot supply from either Enscribe or NonStop SQL DDL, such

as the screen field name and video attributes for the data fields.