Question: How does DynamoDB handle data changes?

Answer

DynamoDB handles data changes in a few different ways depending on the type of change being made.

1. Put and Update operations: When you use the Put operation to add a new item to a table or use the Update operation to modify an existing item, DynamoDB updates the item in the table. These operations are atomic, meaning they update the entire item in a single operation, and the updates are immediately visible to all users.
2. Delete operations: When you use the Delete operation to remove an item from a table, DynamoDB physically removes the item from the table. These operations are also atomic, meaning they remove the entire item in a single operation, and the deletes are immediately visible to all users.
3. Conditional writes: DynamoDB also allows you to perform conditional writes, which only update or delete an item if certain conditions are met. For example, you can use a conditional write to only update an item if its attribute has a certain value or delete an item if it hasn't been modified in a certain amount of time.
4. Versioning: DynamoDB provides a " versioning " feature that allows you to enable versioning on your table. With versioning, DynamoDB automatically keeps a history of all the versions of an item, and you can easily access the previous versions of an item.
5. Eventual consistency: DynamoDB is designed with a distributed architecture, and it replicates data across multiple servers to ensure durability and availability. In some rare cases, when there is a change to an item, it may take some time for the change to propagate to all the copies of that item. This is known as "Eventual consistency, " a trade-off for high availability and scalability.

It's important to keep in mind that when you're making changes to a DynamoDB table, you should be mindful of your table's performance and capacity and ensure that your updates and deletes are properly monitored and tested.