− This specifies the name of the table associated with the trigger. − This specifies the column name that will be updated. Event logging and storing information on table accessĬREATE TRIGGER trigger_nameĬREATE TRIGGER trigger_name − Creates or replaces an existing trigger with the trigger_name.Generating some derived column values automatically.
Triggers can be written for the following purposes − Triggers can be defined on the table, view, schema, or database with which the event is associated.
Triggers are, in fact, written to be executed in response to any of the following events −Ī database manipulation (DML) statement (DELETE, INSERT, or UPDATE)Ī database definition (DDL) statement (CREATE, ALTER, or DROP).Ī database operation (SERVERERROR, LOGON, LOGOFF, STARTUP, or SHUTDOWN). Triggers are stored programs, which are automatically executed or fired when some events occur. In this chapter, we will discuss Triggers in PL/SQL.
