What You Should Know Before Starting with DynamoDB - YugabyteDB

## The Bad ### 5. Cost Effectiveness As highlighted in The Million Dollar Engineering Problem, DynamoDB’s pricing model can easily make it the single most expensive AWS service for a fast growing company. Here are the top 6 reasons why DynamoDB costs spiral out of control. **Over-provisioning to handle hot partitions** … **Cost explosion for fast growing datasets** The post You probably shouldn’t use DynamoDB highlights why DynamoDB is a poor choice for fast growing datasets. As data grows, so do the number of partitions in order to automatically scale out the data (each partition is a maximum of 10GB). However, the total provisioned throughput for a table does not increase. Thus, the throughput available for each partition will constantly decrease with data growth. To keep up with the existing rate of queries, the total throughput would have to be continually increased, increasing the total cost multi-fold! … ## The Ugly ### 10. Strong Consistency with High Availability In terms of the CAP theorem, DynamoDB is an available and partition-tolerant (AP) database with eventual write consistency. On the read front, it supports both *eventually consistent* and *strongly consistent * reads. However, strongly consistent reads in DynamoDB are not highly available in the presence of network delays and partitions. Since such failures are common in multi-region/global apps running on public clouds such as AWS, DynamoDB tries to reduce such failures by limiting strongly consistent reads only to a single region. This in turn makes DynamoDB unfit for most multi-region apps and an unreliable solution for even single-region apps.