A DynamoDB table serves extremely read-heavy item lookups and needs microsecond-level read latency with zero application code changes. What should be deployed?
A.ElastiCache for Redis in front of DynamoDB
ElastiCache works but requires app-level cache logic — DAX is transparent.
B.DAX (DynamoDB Accelerator)
DynamoDB-native cache, code-transparent. Correct.
C.DynamoDB Global Tables
Global Tables = multi-region replication, not read latency caching.
D.Read replicas on the table
DynamoDB doesn't use read replicas — that's an RDS concept.
Why this answer
DAX is DynamoDB's purpose-built in-memory cache — microsecond reads, fully managed, API-compatible (just change the endpoint). ElastiCache requires writing cache logic yourself. Global Tables is multi-region; DynamoDB has no read replicas.
Correct answer: B · Last reviewed 2026-11-02
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