lost-update

Precondition request for Laravel

HTTP optimistic concurrency control for Symfony and Doctrine using strong ETags, If-Match, and ORM versioning.

Deterministic race-condition testing for PostgreSQL-backed services. A wire-protocol proxy explores how transactions interleave and finds double spends, lost updates and deadlocks, with exact replay. No code changes, any language.

Lost update under contention and three ways to close the gap: atomic UPDATE, pessimistic lock (SELECT ... FOR UPDATE) and optimistic lock (@Version + bounded retry). Spring Boot 4, Spring Data JPA, PostgreSQL, with a bench that measures all of them on the same row.

a simple implementation of lost update mechanism of multi-threading using Threading class of C#

Hands-on database engineering study focused on ACID transactions, concurrency control, isolation levels, locking, deadlocks, MVCC, query optimization, and production-grade transaction design using MySQL InnoDB.