Introduction to SQL triggers and their advantages and disadvantages

1. Introduction to SQL triggers:

SQL triggers are a set of SQL statements stored in the database directory. A SQL trigger is executed or fired whenever an event associated with a table occurs, such as an insert, update, or delete.

SQL trigger is a special type of stored procedure. This is special because it is not called directly like a stored procedure. The main difference between triggers and stored procedures is that triggers are automatically called when a data modification event is performed on the table, while stored procedures must be called explicitly.

It is important to understand the advantages and disadvantages of SQL triggers so that you can use it appropriately. In the following sections, we will discuss the pros and cons of using SQL triggers.

2. Advantages of SQL triggers

• SQL triggers provide an alternative method of checking data integrity.

• SQL triggers can capture errors in business logic in the database layer.

• SQL triggers provide another way to run scheduled tasks.

• By using SQL triggers, you do not have to wait for scheduled tasks to run because triggers are automatically called before or after changes are made to the data in the table.

• SQL triggers are very useful for auditing changes to data in tables.

3. Disadvantages of SQL triggers

• ##SQL triggers can only provide extensions Validation, and all validations cannot be replaced. Some simple verification must be done at the application layer. For example, you can use JavaScript or Server Side using a Server Side Scripting Language (such as JSP, PHP, ASP.NET, Perl, etc.) to validate user input from the client.

• Called and executed from the

  client application The SQL trigger is not visible, so it is difficult to figure out the database layer ## What happens in #.

• SQL triggers

  may increase the overhead of the database server.

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