Question: Can DynamoDB do aggregations?

Answer

A simple answer is that DynamoDB does not support aggregations. Since DynamoDB is a NoSQL database and it has very limited query functionality. So it is impossible to perform aggregation from a DynamoDB table by directly calling the DynamoDB API.

But there are a few tools and techniques to achieve the aggregations:

• Perform a table scan and apply the logic on the application side to do the aggregation functions. But this is not a practical solution for the larger dataset.
• Use a materialized index on DynamoDB. The maximum number of entries could be stored in a separate table and updated as new records are added if your table is write-only and does not allow changes or deletions. This strategy isn't a universal fix, although it can work in some limited situations.
• Use Amazon Redshift to perform analytics.
• Utilize DynamoDB streams to perform data aggregation asynchronously and query an aggregated table to retrieve the aggregated data.