Introduction to SQL Events
Introduction to SQL Events
An event is a notification from the database system that a certain defined situation has occurred. Every event is defined by properties such as name and priority and belongs to an event category. The values that determine when an event of a certain category is triggered are stored in the system.
MySQL Events are tasks that run according to a schedule. Therefore, we sometimes refer to them as scheduled events. When you create an event, you are creating a named database object containing one or more SQL statements to be executed at one or more regular intervals, beginning and ending at a specific date and time
A trigger is a special type of stored procedure that automatically runs when an event occurs in the database server. DML triggers run when a user tries to modify data through a data manipulation language (DML) event. DML events are INSERT, UPDATE, or DELETE statements on a table or view.
- For example, you can create an event to optimize all tables in a database, scheduling it to run at 1:00 AM every Sunday.
- Events are also known as “temporal triggers” because they are triggered by time, not by the changes made to tables like triggers Links to an external site..
What is the difference between an event and a trigger in SQL?
Triggers can be used to automatically run certain a pre-defined set of actions before or after the INSERT, UPDATE, and DELETE SQL commands for verification of modification purposes, while events can be used to automatically run a pre-defined set of actions at a scheduled time for data archive and log cleansing purposes.