SOA-C02 Cost and Performance Optimization Practice Question

A company has an Amazon DynamoDB table that stores historical data. The table is accessed infrequently but when queried requires consistent single-digit millisecond latency. The SysOps administrator wants to minimize storage costs while maintaining the required performance. Which DynamoDB table class should the administrator use?

⚠ Common exam trap

Test-takers frequently confuse DynamoDB table classes (Standard vs Standard-IA) with billing modes (On-Demand vs Provisioned), leading candidates to choose a billing mode instead of the correct table class for storage cost optimization.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

DynamoDB Standard-IA (Infrequent Access)

DynamoDB Standard-IA (Infrequent Access) is designed for tables that are accessed less than once per month, offering lower storage costs than DynamoDB Standard while maintaining the same single-digit millisecond latency for queries. Since the table stores historical data with infrequent access but requires consistent performance, Standard-IA minimizes storage costs without sacrificing latency.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

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DynamoDB Standard
Why it's wrong here
DynamoDB Standard is the default table class, optimized for workloads with frequent read/write access to "hot" data. It carries the full storage price with no infrequent-access discount, so using it for historical data that is rarely queried means paying a premium for performance you don't actually use. Because DynamoDB does not automatically move data between table classes based on access patterns, an IT team must intentionally select Standard-IA to avoid the higher storage cost of Standard.
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DynamoDB Standard-IA (Infrequent Access)
Why this is correct
DynamoDB Standard-IA (Infrequent Access) is a table class designed specifically for data that is read infrequently but still requires DynamoDB's single-digit millisecond latency and full durability. It reduces storage costs by roughly 60% compared to Standard, while adding a small per-GB retrieval fee that only applies when data is actually read. This makes it the ideal choice for historical data that is stored long-term and accessed occasionally, since the storage savings outweigh the modest retrieval charges.
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DynamoDB On-Demand
Why it's wrong here
DynamoDB On-Demand is a capacity mode that charges per read/write request and is intended for unpredictable, spiky workloads where capacity planning is impractical. It does not include a storage-class discount; storage is billed at the Standard table class rate regardless of access frequency. For historical data with predictable infrequent access, On-Demand's higher per-request pricing makes it more expensive than a Provisioned or Standard-IA configuration, especially when the dominant cost is long-term storage, not request volume.
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DynamoDB Provisioned
Why it's wrong here
DynamoDB Provisioned is a capacity mode where you pay for reserved read/write capacity units, independent of how much you actually use; this can lead to wasted spend from over-provisioning or throttling risks from under-provisioning. However, Provisioned is about throughput control, not storage cost — it does not reduce the per-GB storage fee, and it requires ongoing capacity monitoring and adjustments. While you can combine Provisioned with the Standard-IA table class, the Provisioned mode alone does not address the core need here: minimizing storage costs for infrequently accessed historical data.

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SOA-C02 Cost and Performance Optimization Practice Question

Why each option matters

Option-by-option breakdown

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