What are MySQL triggers and the triggering events associated with them?

#Basically, a MySQL trigger is a set of statements stored in a database directory. This database object is always associated with a table that is defined to be activated when a specific type of event occurs in that table. In another sense, we can say that MySQL trigger is a special stored procedure. The main difference from a stored procedure is that it is not called directly like a stored procedure. It is called automatically when data modification occurs (even for tables). A trigger can execute when you run one of the following MySQL statements on a table: INSERT, UPDATE, , and DELETE, and it can be called before or after an event. Triggers appear to execute silently, and users don't even know they exist. They cannot contain COMMIT or ROLLBACK statements.

A trigger event is basically an action of time, i.e. when the trigger is activated. The following are the firing events related to MySQL triggers -

• INSERT - As the name suggests, this means that the firing event is related to inserting data into the MySQL table. In this case, the trigger will be fired before or after the data is inserted.
• DELETE -As the name suggests, this indicates that the trigger event is related to deleting data in the MySQL table. In this case, the trigger will fire before or after the data is deleted.
• UPDATE - As the name suggests, this indicates that the triggering event is related to the update of data in the MySQL table. In this case, the trigger will fire before or after the data is updated.

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