Database Insights

Design Cassandra tables around query patterns, not entities. Covers partition key cardinality, hot partition prevention, time bucketing, and secondary indexes vs materialized views.

DynamoDB and MongoDB are the two most common NoSQL choices, but cost structures, query flexibility, and operational overhead differ dramatically depending on your access patterns.

MongoDB 8.0 brings significant replication improvements including faster elections, durable oplog writes, and changes to write concern behavior. Here's what changed and how to take advantage of it.

MongoDB indexes fragment over time as documents are inserted, updated, and deleted. Here's how to detect fragmentation, measure its performance impact, and rebuild indexes safely.

Day-to-day MongoDB replica set operations: adding/removing members, triggering elections, diagnosing replication lag, and managing oplog size.

An honest comparison of MongoDB and PostgreSQL in 2026 — document model vs relational model, JSONB as a document store, ACID transaction trade-offs, horizontal scaling, licensing, and migration paths.

Redis hit maxmemory and evicted your session keys because the application stored 8KB JSON blobs instead of 200-byte hashes. Learn to audit memory usage, use compact encodings, and configure the right eviction policy.

MongoDB's flexible schema allows fields to be null, explicitly set to null, or simply absent — and these three states behave differently in queries, aggregations, and indexes.

Understand the Redis fork landscape after licensing changes. Compare Redis and Valkey features, licensing implications, migration paths, and community support.

Migrate from Redis to Valkey — compatibility, performance benchmarks, and what changes for operators

Downgrading MongoDB requires careful planning — setting the Feature Compatibility Version before replacing binaries, handling replica set members in sequence, and verifying data integrity throughout.

MongoDB's indexing system supports single-field, compound, multikey, text, geospatial, and partial indexes. Choosing the right index type and key order determines whether your queries use microseconds or seconds.