When comparing ArangoDB vs DynamoDB, the Slant community recommends ArangoDB for most people. In the question“What are the best NoSQL databases for web applications?” ArangoDB is ranked 6th while DynamoDB is ranked 12th. The most important reason people chose ArangoDB is:
You can model your data as documents or as a graph - no data model lock-in. You can even combine both models and use them in a single AQL query.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Document and graph-orientend
You can model your data as documents or as a graph - no data model lock-in. You can even combine both models and use them in a single AQL query.
Pro Supports joins
Unlike many NoSQL databases, ArangoDB does support joins in AQL queries.
Pro JavaScript-API
You can extend ArangoDB using JavaScript that runs directly on the Server (Google V8). You can build data-centric microservices that aggregate, validate, transform or enrich data (It's up to you, plain JavaScript) and provide those via a custom API route.
Pro Transaction save
You can use ACID Transactions for short and small data retrieval and/or modification operations in ArangoDB.
Pro Easy cluster setup
Pro Powerful Java Driver (Sync & Async)
ArangoDB has a very good Java Driver for synchronous and asynchronous. In addition the team there is working on a Spring Data integration.
Pro Free tier
DynamoDB offers a free tier which allows up to 40 million database operations a month for free.
Pro Trigger tasks (AWS Lambda) on write
When a new record is written, it can trigger one or many AWS Lambda functions. With Lambda functions in Java, JavaScript, and Python and the other con of "Easy integration with other Amazon services", Lambda functions may be all you need to process the events. This is particularly useful for creating projections (often as other DynamoDB tables) and other read models in a CQRS pattern.
Pro High uptime
Data hosted on DynamoDB is automatically replicated across multiple AWS availability zones, this way the data is protected from any malfunction that may cause loss and it also ensures high uptime.
Pro Easy integration with other Amazon services
Since it's part of AWS, like with other services that Amazon provides, it's very easy to integrate DynamoDB with any other AWS service that you may be using.
Cons
Con No specific features for Event Sourcing
DynamoDB is just a general purpose NoSQL database; hence, there are no features specific to the domain of Event Sourcing, such as event ordering or projections. As a developer, you will need to decide how to implement these.
Con Poor documentation
In true AWS fashion, the documentation for DynamoDB is not top notch. While the learning curve is generally very soft and it's not hard to learn, you need to have at least some experience with cloud and database management to be able to start using DynamoDB and understand the documentation.