How to evaluate and choose data storage systems and architectures based on workload characteristics and business constraints. Coverage includes differences between relational and nonrelational families such as document stores, key value stores, wide column stores, graph databases, time series databases, and search engines; mapping query patterns and latency requirements to storage options; trade offs between strong consistency and eventual consistency and their impact on availability and complexity; partition key design, replication strategies, and high availability considerations; operational concerns including backups, monitoring, vendor and cost trade offs, migration or hybrid strategies, and when to adopt polyglot persistence. Senior level discussion includes selecting specific managed services and reasoning about expected load patterns, failure modes, and operational burden.
MediumTechnical
42 practiced
You are building a social platform with features: authentication, user profiles, friend-graphs, posts, comments, and analytics. Propose a mapping of data stores (relational, document, graph, key-value) to each feature and justify your choices based on query patterns, transaction needs, and scalability. Mention where caching or search should fit.
MediumTechnical
44 practiced
You ingest time-series metrics from 5,000 IoT devices at 100 events per second each. Propose a partitioning and retention strategy to avoid hot shards, support efficient per-device range queries, and enable downsampling and cold storage. Include database choices and shard key design.
MediumTechnical
37 practiced
Design storage and consistency requirements for a chat application where message order per conversation must be preserved, offline clients must sync reliably, and latency must be low. Compare choices: relational DB, Cassandra, DynamoDB, and Redis Streams, and describe conflict resolution and message deduplication strategies.
HardTechnical
36 practiced
Compare Cloud Spanner and CockroachDB for a globally distributed financial ledger that requires strong consistency and horizontal scalability. Discuss latency implications, transactional semantics, schema/sql compatibility, operational burden, disaster recovery, and vendor lock-in concerns.
EasyTechnical
36 practiced
Explain the primary differences between relational databases and non-relational (NoSQL) families. Cover schema (fixed vs flexible), query patterns (joins vs denormalization), transactions, indexing, horizontal scaling, typical web application use cases, and operational considerations a full-stack developer should weigh when selecting one for a feature.
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