Triggers in Oracle

Hi Stephen,

You can look at our recommended articles at the right for more information and articles on Trigger in Oracle. Following is a small example:

CREATE OR REPLACE TRIGGER tableChangesTrigger
BEFORE DELETE OR INSERT OR UPDATE ON MyTable
FOR EACH ROW
WHEN (new.col1 > 0) -- This is condition to start trigger processing, you can check for key value here
DECLARE
mvar number;
BEGIN
mvar := :new.col1 - :old.col1; -- :new. will give new values and :old. will give old values
dbms_output.put('Old value: ' || :old.col1);
END;

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