REP009 Access Routes and Predetermined Join Fields

Visual LANSA

REP009 - Access Routes and Predetermined Join Fields

 

LANSA uses access routes to describe relationships between files in a database. Access routes are simply descriptions which answer questions such as "How do I access the associated records in file B, given that I have a record from file A?" They have no physical impact on the database.

A predetermined join field (PJF) is a special kind of virtual field based on access routes whose value is determined by a field in another file. (Ordinary virtual fields are always based on fields within its own file definition.)

Objectives:

  • To create an access route to define the relationships between the Department and Employee files
  • To show how to create and maintain predetermined join fields (PJFs).
  • To add a calculated predetermined join field to the Department File based on the fields in the Employee file.
  • To add a file lookup Predetermined Join Field to the Employee File based on the fields in the Department file.

To achieve these objectives, you will complete the following:

Step 1. Understand the Database Relationship

Step 2. Create Access Route from Department File

Step 3. Create Access Route from Employee File

Step 4. Create Fields in the LANSA Repository

Step 5. Add File Lookup PJF to Employee File

Step 6. Test New PJF in Employee File

Step 7. Add PJFs to Department File

Step 8. Modify Test Form

Summary

Before you Begin

In order to complete this tutorial, you must have completed the previous tutorials.