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Class Definition Reference
Trigger Definitions
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InterSystems: The power behind what matters   

Describes the structure of a trigger definition.
Triggers are code segments executed when specific events occur in InterSystems SQL. InterSystems IRIS supports triggers based on the execution of INSERT, UPDATE, and DELETE commands. The specified code will be executed either immediately before or immediately after the relevant command is executed, depending on the trigger definition. Each event can have multiple triggers as long as they are assigned an execution order.
You can add trigger definitions to persistent classes. They are not meaningful in other kinds of classes.
A trigger definition has the following structure:
/// description 
Trigger name [ keyword_list ]  
{ implementation }
/// This trigger updates the LogTable after every insert
Trigger LogEvent [ Event = INSERT, Time = AFTER ]
    // get row id of inserted row
    NEW id
    SET id = {ID}

    // INSERT value into Log table
    &sql(INSERT INTO LogTable (TableName, IDValue) VALUES ('MyApp.Person', :id))
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