Scenario: You are conducting scalability testing on a cloud-based database system. During the test, the system exhibits unexpected behavior when the number of concurrent users exceeds a certain limit. What actions should you recommend to improve scalability?

To improve scalability, particularly when facing issues with increasing concurrent users, horizontal scaling is a recommended approach. Horizontal scaling involves adding more machines or instances to distribute the workload, allowing the system to handle increased traffic effectively. By horizontally scaling the cloud-based database system, you can distribute the load across multiple resources, thus enhancing scalability and accommodating a larger number of concurrent users.