Pathmaker Programming Guide

Defining Data for a Pathmaker Project
Preparing for Pathmaker Application Development
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Note If you are keeping a master edit copy of DDL for your project, you can manually apply output update file
changes to your master file or you can use the ?DDL command to obtain a new master file after you have
made all changes.
OUTPUT UPDATE file is composed of three sections:
DELETE statements to delete any objects that directly or indirectly refer to the specified object.
A statement to redefine the specified object.
One section for each statement needed to rebuild the objects deleted in the first section—those
objects that refer to the specified object.
Generating Data Declarations
You can also use the DDL compiler to translate the contents of the schema into data
declarations for COBOL, C, and other languages. The data declarations can be stored
in a file and used when application developers create services for this project.
Additional NonStop SQL Tasks
Additional tasks for describing data for a Pathmaker application that accesses a
NonStop SQL database include:
Registering the NonStop SQL tables and views used by this application through
the SQL Table Registration screen. This step is required.
Describing access paths for tables and views used by the application through the
Table Access Paths screen. This step is optional.
PMADL as well as the full screen interface can be used to accomplish these tasks.
Registering NonStop SQL Tables
After you have created the NonStop SQL database, you are ready to register the tables
on the SQL Table Registration screen in the Pathmaker full screen interface. The SQL
Table Registration screen allows you to specify a DEFINE name for each table, as well
as a name that the Pathmaker product uses internally to identify a table (SQL table
object name). A NonStop SQL table or view is referred to by its Pathmaker SQL table
object name on Pathmaker screens.
The SQL table object name must be unique among all other SQL table object names, all
service names, all server names, and all DDL definitions and records. The Pathmaker
product checks for the uniqueness of the name when you first add the SQL table object
name; however, the Pathmaker product cannot prevent you from adding a DDL
definition or record name that conflicts with an existing Pathmaker object name. If
you do create a conflicting name, the SQL object name will be used instead of the DDL
name.