Global Tables

Companies that use DynamoDB can face two significant challenges. The first is related to replication. For different reasons, companies sometimes need to have their data replicated across multiple regions. The second challenge arises when a company has clients worldwide. In this scenario, latency plays an important role in the user experience. For this reason, it’s interesting to have different database replicas close to clients’ locations. In this lesson, we’re going to explore an interesting solution provided by AWS to tackle these challenges.

What are global tables?

Global tables are a feature that DynamoDB provides for companies that want to replicate their information across multiple regions. By just carrying out a few steps, it’s possible to create replicas of tables in multiple regions across the globe. In doing so, companies are able to improve latency due to the fact that they’ll have table replicas near their clients’ locations.

How do global tables work?

When a table is configured to have global replicas, AWS will make use of a feature called DynamoDB streams to keep replicas in sync. Overall, a DynamoDB stream is a stream of messages where replicas can write to or read from in order to propagate changes. It’s worth clarifying that due to this behavior, replication is eventually consistent.