What is DynamoDB from Amazon? All you need to know

DynamoDB is a fully managed, serverless NoSQL database developed by Amazon. Its seamless scaling, millisecond response times, minimal operational effort, and easy AWS integration are key advantages. Use cases range from software development to scaling gaming platforms and real-time video streaming.

What is DynamoDB?

Amazon DynamoDB is a serverless NoSQL database service for modern applications of any scale and has been provided by AWS (Amazon Web Services) since 2012. Unlike many competitors, DynamoDB is a fully managed solution. As a result, there is no need to handle tasks like upgrades, updates, or scaling. The database management system also offers a wide range of security features and compliance standards. Furthermore, DynamoDB seamlessly integrates with other AWS services like Lambda or the Amazon OpenSearch Service.

Structure of DynamoDB

The database structure features a clear hierarchy with tables as the top entities, without strict relationships between them, unlike relational databases. Amazon DynamoDB stores data in partitions, which are automatically replicated. Each partition consists of three nodes, each holding a copy of the data, enabling easy scaling and providing redundancy in case of a node failure. Developers store records as attributes and assign a unique primary key to them. The database supports both key-value data models and document-oriented models.

Table classes in AWS DynamoDB

By using table classes, the performance and cost structure of DynamoDB tables can be optimised. Users can choose between two classes and switch between them twice within 30 days without downtime to adjust costs to usage patterns.

• DynamoDB Standard is designed as the default table class for high-performance workloads and tables with unpredictable workloads. In comparison, standard tables are characterised by lower costs for read and write operations.
• DynamoDB Standard Infrequent Access is optimised for tables where storage is the major cost factor. IA standard tables offer lower storage costs. The class is also ideal for tables with data that is rarely accessed.

What features does DynamoDB offer?

DynamoDB offers a variety of powerful features that enable scalable, highly available, and responsive applications. The following overview summarises the key features:

• Key-Value and Document Data Models: The database features a flexible schema that allows assigning many different attributes to individual items.
• ACID Transactions: The NoSQL database provides transactions with Atomicity, Consistency, Isolation, and Durability—known as ACID—for a wide range of applications. This makes it possible to extend the scalability and performance of DynamoDB to a broader range of business-critical processes.
• Global tables with active-active replication: DynamoDB global tables are multi-active, allowing users to write to and read from any replica. The capacity is automatically adjusted to regional workloads.
• DynamoDB Streams: This feature captures change data. When an item is created, updated, or deleted in a table, DynamoDB Streams records the event and stores it for 24 hours.
• Secondary indexes: DynamoDB allows both local and global secondary indexes to enable queries using alternative keys. Optionally, they can be implemented as sparse indexes to specifically index only subsets of the data.
• Automatic partitioning: Data is automatically distributed across multiple partitions and scaled as needed.
• Security features: The database offers extensive features to ensure the security of your data. These include granular access controls, encryption at rest, point-in-time recovery, on-demand backups, and private network connectivity.
• Capacity models: Users have the option to choose between an on-demand capacity mode and a provisioned capacity mode.
• DynamoDB Accelerator (DAX): This is an optional service for improved caching that boosts performance up to ten times.

Advantages and disadvantages of Amazon DynamoDB

Amazon’s NoSQL service DynamoDB impresses mainly with the following:

• Automatic scaling: AWS DynamoDB dynamically adjusts capacity and partitioning to match throughput, enabling limitless horizontal growth.
• Serverless architecture: The database management system is fully managed. This allows users to focus entirely on application development rather than having to concentrate on the underlying infrastructure.
• High availability: Multi-region databases and automatic replication ensure availability of up to 99.999 %.
• Low latency: The NoSQL database provides read and write access with single-digit millisecond latency by default. With the DynamoDB Accelerator, response times can even be reduced to the microsecond range if needed.
• Simple AWS integration: The seamless integration of AWS services like CloudWatch or Kinesis expands the functionality of DynamoDB and enables additional data analyses.

Although the advantages clearly outweigh and DynamoDB is definitely among the best SQL alternatives, the platform also has some weaknesses. On one hand, the database offers only limited query options, which are less comprehensive than many competing offerings. On the other hand, the tight integration with AWS services makes migration to other platforms more difficult. With on-demand models, there is also the risk that spikes in demand can lead to unpredictably high fees.

What application areas is DynamoDB suitable for?

DynamoDB was specifically designed for workloads where enormous amounts of data need to be processed, scaled, and provided with very low latency and high availability. Typical use cases include:

• Serverless web applications and mobile backends, where account data, sessions, and configurations are retrieved with minimal latency
• Gaming platforms, where hundreds of thousands or millions of users access game servers simultaneously
• Content streaming for a global audience with uneven or burst traffic
• Banks and financial services companies, which need to process many transactions simultaneously and in real-time, while also facing the challenge of ensuring the timeliness and security of financial transactions
• IoT Applications (IoT = Internet of Things), that process and store sensor data on a large scale

The most important alternatives to DynamoDB

In addition to DynamoDB, there are other database systems that might serve as alternatives depending on requirements, data model, scaling, and infrastructure. These primarily include:

• MongoDB: High flexibility and limitless scalability

• MySQL: Relational system with top-notch availability

• MariaDB: Open-source alternative to DynamoDB

• PostgreSQL: Relational database solution with support for non-relational data types

• Firebase by Google: An excellent alternative, especially for mobile and web applications

• Apache Cassandra: Particularly ideal for large volumes of data

What advantages the individual DynamoDB alternatives offer in detail is discussed in the linked guide.