A database trigger is a stored procedure that automatically executes whenever an event occurs. The event may be insert-delete-update operations. Oracle initiates an ‘AFTER INSERT’ trigger after an insert event has been occurred and an ‘AFTER UPDATE’ trigger after an update event has been occurred.

Knowing how to copy existing table data is beneficial to any DBA. This tutorial will demonstrate how to copy an existing table’s data into a new table. Examples with walkthrough explanation are provided.

In Oracle, you can create an auto increment field using ‘sequence’ database object that can be assigned as primary keys. Using Oracle ‘sequence’ object, you can generate new values for a column. An Oracle sequence is an object like a table or a stored procedure. Examples with walkthrough explanations are provided.