Databases
3 engineering logs on Databases. Newest first.
- Decoding isolation levels: I built a toy DB to force dirty reads and phantom reads
Why the ANSI isolation table does not describe your database, what a phantom read actually is at the index level, and why snapshot isolation still lets two correct transactions corrupt each other.
- AI agents break connection pooling by holding the slot while they think
Agents keep pooled DB connections open for LLM inference, exhausting pools and evicting buffer cache. Decouple reasoning from data, route agents to replicas, and never hold a connection across an inference call.
- The RUM Conjecture: You Cannot Optimize Reads, Updates, and Memory at Once
How the RUM Conjecture explains real-world database trade-offs between read latency, write throughput, and memory overhead across B-Trees, LSM-Trees, and hash indexes.