SQL injection poses a significant threat to application databases by allowing attackers to execute harmful code, potentially leading to data breaches and loss of user trust. A tutorial demonstrates how to utilize automated testing within a continuous integration (CI) pipeline to identify vulnerabilities that permit such attacks. By cloning a demo Node.js project, users learn to test endpoints for exposure threats using tools like Jest and Supertest, and to address SQL injection vulnerabilities through safer coding practices such as using placeholders in SQL queries. The tutorial also guides users on setting up automated testing using CircleCI, ensuring that updates to the code automatically trigger tests to safeguard against SQL injection attacks. It emphasizes the importance of running these tests in a staging environment to protect production databases while encouraging the application of these practices to other projects.