Question 277 - DBS-C01 discussion

Explanation from Amazon documents:Amazon S3 Standard-Infrequent Access (S3 Standard-IA) is a storage class for data that is accessed less frequently, but requires rapid access when needed. S3 Standard-IA offers the high durability, throughput, and low latency of S3 Standard, with a low per GB storage price and per GB retrieval fee1. S3 Standard-IA is designed for long-lived and infrequently accessed data. Examples include disaster recovery, backups, and long-term data retention1.Amazon Athena is an interactive query service that makes it easy to analyze data in Amazon S3 using standard SQL. Athena is serverless, so there is no infrastructure to manage, and you pay only for the queries that you run2. Athena scales automatically---executing queries in parallel---so results are fast, even with large datasets and complex queries2.The news portal can use S3 Standard-IA to store its metadata about posts and comments, which are not frequently looked up or updated. This way, the portal can benefit from the low storage cost of S3 Standard-IA ($0.0125 per GB per month) and the high durability and availability of S31. The portal can also use Athena to query the data stored in S3 using SQL, without having to set up any servers or databases. The portal only pays for the amount of data scanned by each query ($5 per TB scanned) and can optimize the query cost by partitioning, compressing, and converting the data into columnar formats2.Therefore, option C is the most cost-effective solution for the news portal's use case. Option A is not cost-effective because DynamoDB on-demand capacity mode charges for read and write requests ($1.25 per million read requests and $1.25 per million write requests), regardless of how frequently the data is accessed3. Purchasing reserved capacity can reduce the cost, but it requires a minimum commitment of 100 units per region. Option B is not suitable because ElastiCache for Redis is an in-memory data store that provides sub-millisecond latency, but it is more expensive than S3 Standard-IA ($0.046 per GB per hour for cache.t2.micro node type). ElastiCache for Redis is also not designed for long-term data storage, but for caching frequently accessed data. Option D is not available because DynamoDB Standard-Infrequent Access (DynamoDB Standard-IA) is not a valid table class for DynamoDB. The only table classes for DynamoDB are On-Demand and Provisioned.