Internals

You can use DynamoDB without knowing how it works underneath — until a hot partition throttles you, a GSI lags, or adaptive capacity does something you can't explain. This section is the mental model that makes those behaviours predictable instead of mysterious.

It's the deep end of the curriculum: how keys map to physical partitions, how storage and routing actually work, and where today's behaviour comes from historically. Read it after you're comfortable with modelling and indexing — it explains the why behind the rules the earlier sections hand you.

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How DynamoDB Partition Keys Work

How DynamoDB partition keys work — the hash that maps a key to a physical partition, why your key choice decides throughput, and how to dodge hot partitions.

Intermediate7 min read

DynamoDB adaptive capacity

DynamoDB adaptive capacity and burst capacity explained — how DynamoDB absorbs spikes and boosts hot partitions automatically, and where it still can't save you.

Advanced6 min read

How a DynamoDB GSI Is Stored Internally

How a DynamoDB GSI is stored — its own partition space, async replication from the base table, projected attributes, and isolated capacity — explained for SQL minds.

Advanced7 min read

DynamoDB physical partitions

How DynamoDB physical partitions work — the 10 GB, 3000 RCU and 1000 WCU ceilings, how partitions split, and why a hot key throttles with capacity to spare.