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# Why is DynamoDB good for key-value lookups?

* <https://blog.yugabyte.com/a-busy-developers-guide-to-database-storage-engines-the-basics/>
* <https://medium.com/swlh/building-dynamodb-brick-by-brick-237e0008b698>
* <https://engineering.cred.club/dynamodb-internals-90c87184ab88>

DynamoDB uses a B-Tree + a replication log as part of each partition (i.e DB server node)

B-Trees are really good for reads, worse off for writes