The JusDB Database Engineering Blog

Master MySQL performance optimization with this comprehensive 2025 guide. Learn expert techniques for query tuning, indexing strategies, memory configuration, and InnoDB optimization to achieve 10x database performance improvements.

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.

Use StarRocks for high-performance vector search with HNSW indexes. Learn real-time vector ingestion, hybrid queries combining vectors with analytics, and scaling strategies.

MySQL 8.0 end-of-life is April 2026. Plan your upgrade to MySQL 8.4 LTS now. Learn migration strategies, new features, and compatibility considerations.

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

MySQL 8.4 LTS introduces production-optimized InnoDB defaults out of the box. Learn new default values, performance implications, and upgrade considerations.

PostgreSQL's pg_stat_activity view exposes every connection's state — but understanding what 'idle in transaction' means and why it's dangerous requires knowing the full lifecycle of a PostgreSQL backend process.

Use Neon for serverless PostgreSQL — database branching for dev/test, autoscaling, and cost model

TiDB uses Raft consensus protocol through TiKV to replicate every region across three or more nodes. Here's how leader election, log replication, and region management work in practice.

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

TiDB's write path crosses multiple layers — SQL parser, planner, TiKV region leader, Raft log replication, and 2PC commit — before a transaction is durable. Here's a complete walkthrough.

Use Apache Flink CDC to capture MySQL and PostgreSQL changes — stateful processing, exactly-once semantics, and Kubernetes deployment