This article shows you how to use INSTEAD OF TRIGGER to update A noneditioning view A nested table column of a noneditioning view This INSTEAD OF triggers provide a way to modify views that cannot be modified directly through DML statements like INSERT, UPDATE and DELETE An INSTEAD OF trigger is Always a row-level trigger. …
This article shows you how to use BEFORE DELETE TRIGGER, it will fire before the delete operation is executed. In real life scenarios, it is mostly used for purposes like: Restrict invalid DELETE operation. Delete data from another table. 1. Restrict invalid DELETE operation In this example, We have two tables item_details and order_details. The …
Check the USER_TRIGGERS table, you can get the Trigger status easily : — display all triggers for users SELECT TRIGGER_NAME,STATUS FROM USER_TRIGGERS; — display status for a specified trigger SELECT TRIGGER_NAME,STATUS FROM USER_TRIGGERS WHERE TRIGGER_NAME = ‘TRIGGER_NAME’; SELECT TRIGGER_NAME,STATUS FROM USER_TRIGGERS WHERE TRIGGER_NAME IN(‘TRIGGER_NAME_A’, ‘TRIGGER_NAME_B’); Sample data. TRIGGER_NAME STATUS TRIGGER_NAME_A ENABLED TRIGGER_NAME_B DISABLED TRG_BEFORE_EMP_UPDATE ENABLED …
This article shows you how to use BEFORE UPDATE TRIGGER, it’s fire before the update operation is executed. In real life scenarios, it is mostly used for purposes like: Data validation Update values automatically Data logging, or auditing 1. Data Validation Suppose some companies have job openings and already having application data and the criteria …
This article shows you how to use DROP TRIGGER to delete a trigger. — delete a trigger DROP TRIGGER trigger_name; Note In DROP TRIGGER statement, recommend to specify a schema name before trigger name. If you don’t specify a schema name, then database will assume that the trigger is in your own schema. 1. Table …
This article shows you how to use ALTER TRIGGER and ALTER TABLE to enable and disable triggers. — enable / disable a trigger ALTER TRIGGER trigger_name ENABLE; ALTER TRIGGER trigger_name DISABLE; — enable / disable all triggers for a specific table ALTER TABLE table_name ENABLE ALL TRIGGERS; ALTER TABLE table_name DISABLE ALL TRIGGERS; 1. Table …
This article shows you how to use BEFORE INSERT TRIGGER, it’s fire BEFORE an INSERT operation is executed. In real life scenarios, it is mostly used for purposes like Data validation Update values automatically (e.g CREATED_BY, CREATION_DATE etc) 1. Table Create a employee_details, we will try to insert different values into this table and observe …
This article shows you how to use AFTER INSERT TRIGGER, it will fire after the insert operation is executed. 1. After INSERT Trigger In this example, if a new user is created in user_details, but fields like passport_no or driving_license_no is missing, a new record will be inserted into user_reminders via ‘after insert’ trigger on …
The following SQL shows you how to get the source code for a specified trigger : select text from user_source where name =’&trigger_name’ and type =’TRIGGER’; References Oracle database – USER_SOURCE table
This article shows you how to use AFTER UPDATE TRIGGER, it will fire after the update operation is executed. 1. Logging example In this example, after each update on ‘SALARY’ column of employee_salary, it will fire a ‘after update’ trigger and insert the new updated data into a employee_salary_log table, for audit purpose. 1.1 Create …
This article shows you how to use ALTER TRIGGER to rename a trigger. — rename a trigger ALTER TRIGGER original_name RENAME TO new_name; 1. Table + Trigger electricity_bill create table electricity_bill ( bill_id number(5) primary key, amount number(5) ); — Table ELECTRICITY_BILL created. trg_rename_example CREATE OR REPLACE TRIGGER trg_rename_example BEFORE UPDATE OR DELETE OR INSERT …
This article shows you how to use AFTER DELETE TRIGGER, it will fire after the delete operation is executed. In real life scenarios, it is mostly used for purposes like: Auditing or logging 1. After DELETE Trigger In this example, if the user deleted a row of medical_bills, the deleted row will be inserted into …