Query Optimization18 min read
"Push It All on the Database" — The Lie That Works Until It Doesn't
Every team ships with the same lie: throw everything on the database and it'll handle correctness. Works at 50 writes/sec.
Writing
39 long-form articles on production engineering — how real systems fail, why, and what actually fixed them.
18 articles matching “Database”
Architecture Decisions20 min read
How Databases and Servers Shut Down Without Losing Your Data — Signal Handling, Drain, and the 30-Second Clock
Every process you run will be told to stop — the only question is whether it gets a request it can act on or a bullet it never sees coming.
Query Optimization13 min read
“The Money Was There When I Checked” — Transaction Isolation Levels and the Bugs Each One Lets Through
“We sold 3 tickets but only had 1.” The code is inside a transaction, looks right, works a hundred times locally, and only breaks in production under load.
Query Optimization13 min read
Page 1 Loads in 8ms, Page 5,000 Takes 4 Seconds — The OFFSET Trap and How Cursors Fix It
Every list endpoint ends in LIMIT 20 OFFSET ?. It has an index, page one returns in 8ms, and it passes review — then one Tuesday page 4,000 takes four seconds and a nightly export job stops finishing.
Query Optimization15 min read
The Data Structure That Lies to Save Your Disk — How Bloom Filters Say "Definitely Not Here" in 1% of the Space
We're trained to demand our data structures be correct — so here's one that's wrong on purpose, and runs inside Cassandra, RocksDB, Bigtable, most CDNs, and your browser's malware check.
Production Incidents18 min read
When AUTO_INCREMENT Stops Incrementing — The MySQL INT Overflow Anatomy
It's 3 AM. Inserts are failing with 'Duplicate entry 2147483647' — but you never inserted a duplicate. Welcome to one of MySQL's most quietly famous outages.
Picking the Right DB15 min read
How Redis Actually Deletes Expired Keys — The Lazy + Active Hybrid You Didn't Know About
A senior-engineer walkthrough of how Redis really handles TTLs. Why TTL=0 doesn't free memory. The two strategies — lazy (on-access) and active (the random-sample-and-25%-threshold sampler).
Picking the Right DB22 min read
LSM Trees, the Deep Cut — MemTable, WAL, SSTables, Compaction and Why Your Writes Are So Fast
A senior-engineer walkthrough of Log-Structured Merge Trees: MemTable + WAL durability, SSTable layout with sparse index and bloom filters, the L0→Ln level hierarchy, leveled vs tiered vs FIFO compaction, the three…
Architecture Decisions20 min read
Why Your Consistent Hashing Is Still Failing in Prod — and When Range Partitions Are the Right Tool
SVG-backed walkthrough: ring hotspots, successor overload when a node dies, and two ring generations during deploy.
Schema Design14 min read
UUID v4 vs UUID v7 vs Snowflake — Pick the Right Primary Key
A plain-English walkthrough: how B-tree inserts actually work, what a page split costs, why random UUID v4 keys bloat the index by 2× and blow the buffer pool.
Performance14 min read
Connection Pool Sizing: The Math Behind Why Your App Is Slow
Why your connection pool config is probably wrong — and how to fix it with Little's Law, Kingman's Formula, and the process-to-core ratio.
AI Agents18 min read
Two Agents, Two Handoff Rules, Zero Progress: The Deadlock Problem in AI Agent Systems
The Refund Agent will not refund until the carrier confirms the return. The Shipping Agent will not create a return label until the refund is approved.
Production Incidents45 min read
COMMIT Returned OK. After the Power Came Back, the Row Was Gone.
A payment commits, the API returns 200, the rack loses power, and after recovery the row does not exist. Before blaming the database, six questions have to be separated.
Architecture Decisions20 min read
C10K vs C10M: Two Scaling Problems People Confuse for One
A beginner-friendly walkthrough: what “concurrent” means, what the C10K and C10M problems actually are, how the industry usually fixes them (event loops vs whole-system design), and what still goes wrong in production —…
Schema Design12 min read
Stop Using DELETE in Production: Hard Delete vs Soft Delete in High-Concurrency Systems
Why DELETE is the most expensive DML operation in a relational database — and why a simple UPDATE SET deleted_at = NOW() is 4-8x faster under concurrent load.
Query Optimization18 min read
Why Your Indexes Aren't Working: Non-SARGable Queries Explained
A deep-dive into non-SARGable SQL with B-tree diagrams, real EXPLAIN output, and the exact rewrites — told through a gaming dashboard that went from 4,200ms to 2ms without touching the schema.
Query Optimization13 min read
Vector Search Explained: From KNN to HNSW — A Complete Guide
How similarity search works under the hood — and why naive brute-force collapses at scale.
Query Optimization5 min read
MySQL Query Optimization: Real Lessons from a 36GB Index Disaster
What happens when your index outgrows your data — and how we fixed it without downtime in production.