Accessing before and after rows

Accessing before and after rows Many trigger actions need to access the values of the rows being changed. Triggersaccessing before and after rows

Such trigger actions need to know one or both of the following:

the "before" values of the rows being changed (their values before the database event that caused the trigger to fire)
the "after" values of the rows being changed (the values to which the database event is setting them)

provides transition variables and transition tables for a trigger action to access these values. See "Referencing Old and New Values: The Referencing Clause" in the .