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Editor to share with you about the use of mysql triggers, I hope you will learn a lot after reading this article, let's discuss it together!

A trigger is a special type of stored procedure. Triggers are mainly triggered by events (add, delete, change) to be invoked automatically. Triggers are often used to enforce business rules, which are high-level constraints that are executed by event triggers. The stored procedure can be called by the name of the stored procedure.

Trigger is a method that SQL server provides to programmers and data analysts to ensure data integrity. It is a special stored procedure related to table events. Its execution is not called by the program, nor started manually, but triggered by events. For example, when an operation is performed on a table (insert,delete, update), it is activated. Triggers are often used to strengthen data integrity constraints and business rules. Triggers can be found in the DBA_TRIGGERS, USER_TRIGGERS data dictionary. The trigger of SQL3 is a statement that can be automatically executed by the system to modify the database.

Trigger time: specify the trigger time. If specified as BEFORE, it is triggered before the DML operation is executed to prevent certain error actions from occurring or to implement certain business rules; if specified as AFTER, it is triggered after the DML operation is executed to record the operation or do some post-processing.

Trigger event: the event that causes the trigger to be triggered, that is, the DML operation. It can be either a single trigger event or a combination of multiple trigger events (you can only use OR logic combination, not AND logic combination).

After reading this article, I believe you have a certain understanding of the use of mysql triggers, want to know more about it, welcome to follow the industry information channel, thank you for reading!

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