Tag: #database
Writing on GPUs, LLMs, MLOps, Kubernetes — and mindset · 114 posts
A Mid-Course Check on Neo4j's CalVer Era: Block Format, Cypher 25, and How GQL Lands in the Engine
Neo4j switched to calendar versioning in early 2025, and over the roughly 17 months since then has shipped 18 feature releases — with each release's hotfix support ending the moment the next one ships. As of this writing
2026-07-17 · 14 min read #database#neo4j#graph-database#cypher#gqlClickHouse Lazy Materialization — How a LIMIT 10 Trick Grew Into FINAL and JOIN
ClickHouse's lazy materialization is an optimization that skips reading SELECT columns until sorting and LIMIT are finished, and it launched in 25.4 (April 2025) as a conservative feature that only kicked in for LIMIT 10
2026-07-17 · 15 min read #database#clickhouse#olap#query-optimization#performanceCassandra 6.0-alpha1 and Accord Transactions — Where Does the 5-Year "General-Purpose Transaction" Promise Stand Now
Accord, the general-purpose transaction protocol for Cassandra proposed as CEP-15 in 2021, finally shipped in a runnable release, 6.0-alpha1, in March-April 2026. The protocol promises to handle multi-partition strict-se
2026-07-17 · 13 min read #database#cassandra#distributed-systems#transactionspg_plan_advice in Postgres 19: The Compromise From a Project That Has Long Refused Hints
The PostgreSQL project has refused optimizer hints for a long time. But PostgreSQL 19 Beta 1, released on June 4, 2026, added two contrib modules built by Robert Haas: pgplanadvice and pgstashadvice. This isn't Oracle-st
2026-07-16 · 14 min read #postgresql#query-planner#query-optimization#database#performanceThe Version After MySQL 9.7 Is 26.7 — How MySQL and MariaDB Tidied Up Their Release Models in Spring 2026 ♪ Listenable
On April 21, 2026, MySQL 9.7.0 shipped as GA, opening a new LTS line for the first time in almost two years since 8.4 — and that same month, Extended Support for MySQL 8.0 ended, dropping it into Sustaining Support. Then
2026-07-16 · 20 min read #mysql#mariadb#database#versioning#devopsInfluxDB 3 Core's 72-Hour Limit Is Actually a 432-File Limit — The Bill Left by Rewriting Parquet
InfluxDB 3 rewrote its entire engine in Rust and put the storage layer on Apache Arrow and Parquet. It is commonly claimed that Core only queries the last 72 hours, but reading the source shows no such code. What actuall
2026-07-16 · 18 min read #database#influxdb#time-series#parquet#storage-engineDuckDB Gets a Client-Server Protocol — What Quack Changes and What It Doesn't
On May 12, 2026, the DuckDB team announced Quack — a client-server protocol built on top of HTTP that lets two DuckDB instances become client and server to each other, so the same database can be read and written concurr
2026-07-16 · 18 min read #database#duckdb#olap#analytics#data-engineeringpgrust: Postgres Rewritten in Rust, Passing 100% of the Regression Tests — What That Actually Means
Malcolm Matis (malisper) released pgrust, a rewrite of Postgres in Rust. It targets Postgres 18.3 compatibility, passes more than 46,000 regression queries, and boots from an existing 18.3 data directory. This piece is a
2026-07-11 · 6 min read #postgresql#rust#pgrust#database#regression-testsSpinning Up and Killing Postgres on Kubernetes with CloudNativePG — Failover Measured at 23 Seconds
On a real 8-node Kubernetes cluster, I installed CloudNativePG (CNPG) v1.30.0, brought up a 3-instance Postgres cluster, and then actually killed the primary. From bootstrap through replication checks, to failover after
2026-07-11 · 5 min read #cloudnativepg#postgresql#kubernetes#operator#databaseMariaDB Architecture — From Storage Engines to Galera ♪ Listenable
A top-down walk through the MariaDB server architecture, from the connection layer to the parser, optimizer, and executor, covering storage engine selection criteria, replication, the Galera synchronous multi-master clus
2026-06-27 · 20 min read #mariadb#storage-engine#galera#replication#innodbA Deep Dive into PostgreSQL Architecture — From MVCC to Vectors
A deep look at the internal architecture of PostgreSQL, from process and memory structure to MVCC, indexes, query execution, replication, partitioning, and extensions like pgvector. We unpack the core mechanisms with ASC
2026-06-27 · 11 min read #postgresql#database#mvcc#architecture#indexingPostgreSQL Version Upgrade Strategies — pg_upgrade and Logical Replication
A practical comparison of three ways to perform a PostgreSQL major version upgrade: dump/restore, pgupgrade, and logical replication. We cover downtime trade-offs, the pgupgrade --link procedure and its caveats, near-zer
2026-06-16 · 16 min read #postgresql#database#upgrade#pg-upgrade#logical-replicationMigration Incident Case Studies and Checklists — Learning from Others Failures
Migrations are among the most common and most painful sources of outages. This article walks through typical failure modes like lock storms, replication lag, data loss, and irreversible changes, derives causes and lesson
2026-06-16 · 14 min read #database#migration#postmortem#incident#reliabilityThe Expand-Contract Pattern — The Right Way to Change Schemas with Zero Downtime
A thorough walkthrough of the Expand-Contract pattern, the standard technique for changing a live database schema without downtime. We cover per-scenario SQL for adding columns, renaming, dropping, and adding constraints
2026-06-16 · 15 min read #database#migration#zero-downtime#expand-contract#reliabilityAWS DMS in Practice — Migration and Continuous Replication (CDC) ♪ Listenable
A practitioner walkthrough of AWS Database Migration Service from its building blocks to full load and CDC, heterogeneous migration with SCT, LOB handling and data validation, monitoring and cut-over strategy. It also co
2026-06-16 · 19 min read #aws#dms#database#migration#cdcZero-Downtime Data Migration — Moving Data with Dual-Write, Backfill, and CDC ♪ Listenable
Moving data to a new store without stopping the service is tricky because of consistency and ordering guarantees. This post lays out a staged cutover strategy combining Dual-Write, Backfill, and CDC, plus verification, r
2026-06-16 · 21 min read #database#migration#cdc#debezium#dual-writeNoSQL and Heterogeneous Data Migration — Between RDB, MongoDB, and Many Stores
Relational and document stores differ in the data model itself. This article lays out, from a practitioner view, what must be redesigned when moving from RDB to document and back, how to migrate with zero downtime using
2026-06-16 · 16 min read #database#migration#nosql#mongodb#cdcAutomating Database Migrations — Treating Schema as Code with CI/CD and GitOps
The era of applying schema changes by hand is over. This guide lays out the full picture of integrating migrations into your pipeline: linting and dry-running in PRs, applying per-environment automatically, detecting dri
2026-06-16 · 13 min read #database#migration#cicd#gitops#flywayAn Introduction to Database Migration Strategy — Schema, Data, and Zero Downtime
A systematic overview of database migration types and risks, versioned migrations, and zero-downtime deployment principles. It covers transactional DDL, backups and dry runs, environment promotion, team process, and an i
2026-06-16 · 16 min read #database#migration#schema#devops#reliabilityComparing Schema Migration Tools — Flyway, Liquibase, golang-migrate, Alembic, and Atlas
A comparison of the major schema migration tools — Flyway, Liquibase, golang-migrate, Alembic, and Atlas — across their models, version control, checksums, rollback, and CI integration. We examine the difference between
2026-06-16 · 14 min read #database#migration#flyway#liquibase#tooling