Tagged “isolation levels”

Exploration · 30 October 2026

How a database survives a crash

Pull the plug on a database halfway through a write and it comes back with every committed transaction and none of the half-finished ones. How? Follow a write through the log, the buffer pool and the disk, compare B+trees with LSM-trees, watch compaction, and then see the other half of the promise — what concurrent transactions are allowed to see — with real PostgreSQL and SQLite running between the paragraphs.

Data and event platforms Software engineering

Tool · 28 October 2026

Isolation lab

Two or three SQL sessions side by side: step through an interleaving and watch what PostgreSQL or MySQL InnoDB does at each isolation level — results, which statement blocks on which lock, deadlocks, serialization failures (40001 / 40P01) and the final table — with the classic anomalies, their fixes and the Hermitage tests built in, or the same steps on a real Postgres server.

Data and event platforms