Additional Interesting Techniques

IN THIS CHAPTER

• Programmatically Canceling a Query
• Programmatic Equivalent of Cancel Query
• Validation, Navigation, and Simulating Navigation
• Enhancing the Function of Exit Form
• Preventing Validation of WHEN- VALIDATE-ITEM for Control Items During Query Time
• When to Use WHEN-VALIDATE-RECORD and When to Use WHEN-VALIDATE-ITEM
• When to Use the Same Trigger and How to Make It Fire at Multiple Levels
• A Block Level Commit
• Summary

This chapter presents some interesting techniques regarding cancellation of a query programmatically; the processes of navigation and validation; and defining triggers at multiple levels. The initial two sections explain techniques of programmatically canceling a query and the programmatic equivalent of Cancel Query when in Enter Query mode. The following sections explain the processes of validation and navigation with emphasis on two common triggers used for validation: WHEN-VALIDATE-ITEM and WHEN-VALIDATE-RECORD. With reference to this, two special techniques, one concerning an enhanced Exit Form functionality, and the second one on how to avoid the firing of WHEN-VALIDATE-ITEM trigger for control items ”in query time ”are discussed. The subsequent section outlines when to use the same trigger and how to make it fire, at multiple levels. The chapter concludes with a discussion of a block level commit.