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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: SyntaxThe HCL OneDB™ Guide to SQL: Syntax describes the syntax of the statements, data types, expressions, operators, and built-in functions of the HCL OneDB™ dialect of the SQL language.
SQL statementsThis chapter describes the syntax and semantics of SQL statements that are recognized by HCL OneDB™.
CREATE TRIGGER statementUse the CREATE TRIGGER statement to define a trigger on a table. You can also use CREATE TRIGGER to define an INSTEAD OF trigger on a view.
Action Clause
Actions of Multiple Triggers

Actions of Multiple Triggers

When an UPDATE or MERGE statement activates multiple triggers, the trigger actions merge. Assume that taba has columns a, b, c, and d, as this example shows:

CREATE TABLE taba (a INT, b INT, c INT, d INT);

Next, assume that you define trig1 on columns a and c, and trig2 on columns b and d. If both triggers specify BEFORE, FOR EACH ROW, and AFTER actions, then the trigger actions are executed in the following order:

BEFORE action list for trigger (a, c)
BEFORE action list for trigger (b, d)
FOR EACH ROW action list for trigger (a, c)
FOR EACH ROW action list for trigger (b, d)
AFTER action list for trigger (a, c)
AFTER action list for trigger (b, d)

The database server treats all the triggers that are activated by the same triggering statement as a single trigger, and the trigger action is the merged-action list. All the rules that govern a trigger action apply to the merged list as one list, and no distinction is made between the two original triggers.