A company needs to run scheduled jobs that execute SQL queries on their Amazon RDS database every night. Which AWS service provides fully managed job scheduling without maintaining dedicated compute resources?
AWS Lambda integrates natively with Amazon EventBridge Scheduler, which can invoke the function on a fixed schedule (e.g., once daily) without any persistent compute running. Lambda spins up the execution environment only when the event fires, runs the database query, and then shuts down, so you pay only for the milliseconds of compute during the actual invocation. This serverless model perfectly matches the sporadic, short-running nature of a daily batch query and eliminates idle cost. Additionally, Lambda connections to a database can use RDS Proxy or a private VPC setting to manage short-lived connections efficiently.
Why this answer
AWS Lambda triggered by Amazon EventBridge Scheduler is the correct choice because EventBridge Scheduler provides fully managed, serverless job scheduling that can invoke Lambda functions to execute SQL queries on Amazon RDS. This eliminates the need to provision or maintain any dedicated compute resources, as the scheduling and execution are handled entirely by AWS.
Exam trap
The trap here is that candidates may confuse 'fully managed job scheduling' with services like EC2 cron jobs or ECS scheduled tasks, overlooking that EventBridge Scheduler is the only option that requires zero compute resource management for this specific use case.
How to eliminate wrong answers
Option A is wrong because Amazon EC2 with cron jobs requires you to provision, patch, and manage a dedicated EC2 instance, which contradicts the requirement of 'without maintaining dedicated compute resources'. Option C is wrong because Amazon ECS with scheduled tasks still requires you to manage a cluster of EC2 instances (or use Fargate, which is serverless but not the simplest fully managed scheduling service for this use case) and involves container orchestration overhead. Option D is wrong because AWS OpsWorks is a configuration management service (based on Chef/Puppet) that manages EC2 instances and applications, not a simple scheduled job execution service, and it still requires maintaining compute resources.