Question: Does DynamoDB have read replicas?

Answer

DynamoDB has automatically managed storage replicas, but it does not offer RDS-style read-only table replicas that you create inside a Region. There is no DynamoDB feature called "On-Demand Replicas."

Within a Region, AWS replicates table data across multiple Availability Zones. Your application uses one regional service endpoint; it does not pick a storage node, replica endpoint or primary server. Increase read throughput through the table's capacity mode and an effective key design.

For geographically distributed applications, global tables create table replicas in multiple Regions. These replicas accept writes as well as reads. MREC replicates changes asynchronously; MRSC supports strongly consistent reads across its participating Regions, with different feature restrictions. Applications must route requests to the desired Region and plan their failover behavior.

For repeated reads of hot data, DynamoDB Accelerator provides a separate cache cluster with read replica nodes. Those nodes cache DynamoDB data; they are not durable copies of the whole table. DAX accelerates eventually consistent reads, while strong reads pass through to DynamoDB.

A global secondary index is another access path, not a general-purpose read replica. Its data and read capacity are separate, but its reads are eventually consistent and only projected attributes are available.

Source: AWS partition and replication model.