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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.
UPDATE Event

UPDATE Event

UPDATE events (and SELECT events) can include an optional column list.

UPDATE Event


Element	Description	Restrictions	Syntax
column	Column that activates the trigger	Must exist in the triggering table	Identifier
table	Name of the triggering table	Must exist in the database	Identifier

The column list is optional. If you omit the OF column list, updating any column of table activates the trigger.

The OF column clause is not valid for an INSTEAD OF trigger on a view.

An UPDATE on the triggering table can activate the trigger in two cases:

The UPDATE statement references any column in the column list.
The UPDATE event definition has no OF column list specification.

Whether it updates one column or more than one column from the column list, a triggering UPDATE statement activates each Update trigger only once.

The MERGE statement can also activate an Update trigger, if the specified table of a trigger with no columns list is the target table of the MERGE statement, or if the Update clause of the MERGE statement references a column in the column list of the Update trigger.