Dynamodb easy
How can an architect implement a 'Welcome Email' trigger that fires whenever a new user record is created in a DynamoDB table?
- A Use DynamoDB Streams integrated with an AWS Lambda function to catch 'INSERT' events.
- B Set up a CloudWatch alarm that triggers if the table size increases by more than 1KB.
- C Poll the table every 5 seconds using a `Scan` operation from the email server.
- D The email server must also write to a secondary 'Email Queue' table simultaneously (Dual-Write).
Answer: A. Use DynamoDB Streams integrated with an AWS Lambda function to catch 'INSERT' events.
DynamoDB Streams capture every change (Insert, Update, Delete) in near real-time. By connecting a Lambda function to the stream, you create a decoupled, event-driven system where the database change automatically triggers the business logic (the email).
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