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SQL programmingYou can use the HCL OneDB™ implementation of the SQL language to develop applications for HCL OneDB™ database servers.
Guide to SQL: TutorialThe HCL OneDB™ Guide to SQL: Tutorial shows how to use basic and advanced structured query language (SQL) to access and manipulate the data in your databases. It discusses the data manipulation language (DML) statements as well as triggers and stored procedure language (SPL) routines, which DML statements often use.
Create and use triggers
Summary

Summary

To introduce triggers, this chapter discussed the following topics:

The components of the CREATE TRIGGER statement
Types of DML statements that can be triggering events
Types of SQL statements that can be triggered actions
How to create BEFORE and AFTER triggered actions and how to use them to determine the impact of the triggering statement
How to create a FOR EACH ROW triggered action and how to use the REFERENCING clause to refer to the values of columns both before and after the action of the triggering statement
INSTEAD OF triggers on views, whose triggering event is ignored, but whose triggered actions can modify the base tables of the view
The advantages of using SPL routines as triggered actions
Special features of calls to trigger routines as triggered actions
How to trace triggered actions if they behave unexpectedly
How to generate two types of error messages within a triggered action.