Ideal Method for Retrieving DynamoDB Table Changes
Question
An application currently writes a large number of records to a DynamoDB table in one region.
There is a requirement for a secondary application to retrieve new records written to the DynamoDB table every 2 hours and process the updates accordingly.
What would be an ideal method to ensure that the secondary application gets the relevant changes from the DynamoDB table?
Answers
Explanations
Click on the arrows to vote for the correct answer
A. B. C. D.Correct Answer - C.
AWS Documentation mentions the following.
A DynamoDB Stream is an ordered flow of information about changes to items in an Amazon DynamoDB table.
When you enable a stream on a table, DynamoDB captures information about every modification to data items in the table.
Whenever an application creates, updates or deletes items in the table, DynamoDB Streams write a stream record with the primary key attribute(s) of the modified items.
A stream record contains information about a data modification to a single item in a DynamoDB table.
You can configure the stream to capture additional information, such as the "before" and "after" images of modified items.
For more information on DynamoDB Streams, please visit the URL below.
http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Streams.htmlThe ideal method to ensure that the secondary application gets the relevant changes from the DynamoDB table is to use DynamoDB Streams to monitor the changes in the DynamoDB table.
DynamoDB Streams is a feature of DynamoDB that allows you to capture changes made to a DynamoDB table in real-time. When an application writes to a DynamoDB table, DynamoDB Streams can provide a time-ordered sequence of item-level changes that can be consumed by multiple applications. These changes can be used to trigger actions, such as updating a search index or sending a notification to another application.
In this scenario, you can use DynamoDB Streams to capture the changes made to the DynamoDB table and send them to the secondary application every 2 hours. The secondary application can then process the changes accordingly.
Option A, inserting a timestamp for each record and scanning the entire table for the timestamp as per the last 2 hours, is not an efficient solution as it requires scanning the entire table every 2 hours, which could be very time-consuming and expensive.
Option B, creating another DynamoDB table with the records modified in the last 2 hours, is not a scalable solution as it would require duplicating data from the original table to the new table every 2 hours, which could lead to increased storage costs and maintenance overhead.
Option D, transferring records to S3 which were modified in the last 2 hours, is not an optimal solution for this scenario as it requires additional processing to move the data from DynamoDB to S3 and then back to the secondary application.
Therefore, the correct answer is option C, using DynamoDB Streams to monitor the changes in the DynamoDB table.
