Create Triger Example CREATE OR REPLACE TRIGGER my_sal_changes BEFORE DELETE OR INSERT OR UPDATE ON Emp_tab FOR EACH ROW WHEN (new.Empno > 0) DECLARE sal_diff number; BEGIN sal_diff := :new.sal – :old.sal; dbms_output.put(‘Old salary: ‘ || :old.sal); dbms_output.put(‘ New...
The method of setting values via triggers, shown in the preceding section, can be combined with the remote data access methods described in Chapter 25. As with materialized views, you may replicate all or some of the rows in a table. For example, you may want to create and maintain a s...
Example 2. A PL/pgSQL Trigger Procedure For Auditing This example trigger ensures that any insert, update or delete of a row in the emp table is recorded (i.e., audited) in the emp_audit table. The current time and user name are stamped into the row, together with the type of opera...
1. Logging example In this example, after each update on ‘SALARY’ column ofemployee_salary, it will fire a ‘after update’ trigger and insert the new updated data into aemployee_salary_logtable, for audit purpose. 1.1 Create tables and trigger. employee_salary CREATE TABLEemployee_salary (...
In this example, we have created a trigger which will insert rows into an audit table before each updating of transaction table. Whenever user UPDATE data ofbank_transactions, the old data will be inserted intobank_transactions_auditby trigger for audit or backup purpose. ...
Triggers in SQL Server - Learn about SQL Server triggers, their purpose, types, and benefits. Understand DML and DDL triggers with practical use cases.
Test SQL Server Trigger In order to test the SQL Server trigger example, I created three queries. I put the code inside a transaction just to keep order in my test environment, you can omit this. The first of those queries is an update. ...
Example Let's look at an example of how to create an AFTER UPDATE trigger using the CREATE TRIGGER statement. If you had a table created as follows: CREATE TABLE orders ( order_id number(5), quantity number(4), cost_per_item number(6,2), total_cost number(8,2) ); ...
This Oracle tutorial explains how to create a BEFORE INSERT Trigger in Oracle with syntax and examples.Description A BEFORE INSERT Trigger means that Oracle will fire this trigger before the INSERT operation is executed.Syntax The syntax to create a BEFORE INSERT Trigger in Oracle/PLSQL is: ...
次の文は、記憶域の容量が小さく、割当てに制限のあるexample表領域の中にサンプル表employees_demoを定義します。CREATE TABLE employees_demo ( employee_id NUMBER(6) , first_name VARCHAR2(20) , last_name VARCHAR2(25) CONSTRAINT emp_last_name_nn_demo NOT NULL , email VARCHAR2(25) CONSTRAINT...