MMatheusinreleaserun.hashnode.devPostgreSQL Reference: EXPLAIN ANALYZE, Covering Indexes, pg_stat_activity, and Safe DDL MigrationsPostgreSQL diagnostics and the patterns you need before you're staring at production slow queries. psql meta-commands — faster than any GUI \l -- list databases \c mydb -- connect to database \dt -- list tabl...2h ago·2 min read
MMatheusinreleaserun.hashnode.devApache Kafka Reference: acks/min.insync.replicas, Consumer Lag, Exactly-Once, CooperativeStickyAssignorKafka's config options cause more production issues than any other part of it. Here's what actually matters. acks and min.insync.replicas — the durability decision # Producer side acks=all # wait for all ISR replicas (strongest) re...2h ago·2 min read
MMatheusinreleaserun.hashnode.devRedis Reference: ZADD Rate Limiter, Distributed Lock Pattern, Pub/Sub vs Streams, MULTI/EXECRedis commands worth committing to memory. SET with atomic options — the patterns that matter SET session:user:123 "data" EX 3600 NX # set session if not exists (atomic) GETEX session:user:123 EX 3600 # get + reset TTL (sliding expiry) GE...3h ago·2 min read
MMatheusinreleaserun.hashnode.devElasticsearch Reference: Query DSL, Aggregations, ILM, and the text vs keyword DecisionElasticsearch Query DSL and the production patterns worth knowing. Always filter before querying in bool context Filter context is cached and doesn't affect scoring. It's faster: { "query": { "bool": { "must": [ { "match": { "titl...3h ago·2 min read
MMatheusinreleaserun.hashnode.devMySQL Cheat Sheet: EXPLAIN Type Column, Covering Indexes, and Performance SchemaMySQL diagnostics and the patterns you need before you're staring at a slow query in production. EXPLAIN type column — what you're looking at The type column in EXPLAIN tells you how MySQL is scanning the table: typeMeaningAction constPrimary ...3h ago·2 min read
MMatheusinreleaserun.hashnode.devMongoDB Cheat Sheet: Aggregation Pipeline, TTL Indexes, and explain() AnalysisMongoDB cheat sheet covering the commands and patterns I reach for daily. mongosh quick connect mongosh "mongodb://localhost:27017" mongosh "mongodb+srv://user:pass@cluster.mongodb.net/dbname" # Atlas CRUD essentials // Find with operators db.users...3h ago·2 min read
PMPhilip McClarenceinpostgresdba.hashnode.devDebugging Stale Continuous Aggregates in TimescaleDBThe Silent Data Bug: Stale Continuous Aggregates in TimescaleDB There is a class of bug that is worse than a crash: one where everything appears to work perfectly while quietly returning wrong answers. That is exactly what a stale continuous aggregat...6h ago·4 min read
Uultraduneinevalreport.hashnode.devEVAL #002: Vector Databases in 2026 — Qdrant vs Pinecone vs Weaviate vs Chroma vs pgvector vs MilvusEVAL #002: Vector Databases in 2026 — Qdrant vs Pinecone vs Weaviate vs Chroma vs pgvector vs Milvus The AI Tooling Intelligence Report — by Ultra Dune Issue #002 · March 2026 The Vector DB Decision You Keep Avoiding You've built your RAG pipeline. ...20h ago·10 min read
ETEduard Tymchenkoinreleemdev.hashnode.devComplete Guide to MariaDB Logs: Audit, Configuration, and MoreMariaDB logs are a cornerstone of effective database management. They capture critical details about your database’s operations, offering invaluable insights for administrators, developers, and system1d ago·10 min read