What Write Skew Looks Like

This post discusses the concept of Write Skew and Snapshot Isolaation in database transactions. It explains that while Snapshot Isolation is often considered a good balance between performance and correctness, its precise meaning can be unclear. The text delves into the differences between Serializable and Anomaly SERIALIZABLE (SNAPSHOT) isolation levels, highlighting that SNAPSHOT allows for outcomes not possible in either serial execution. It also explores how Snapshot Isolation can lead to non-serializable behavior and what must be done to eliminate these anomalies. The post concludes by emphasizing the importance of understanding Snapshot Isolation given its prevalence in mainstream databases.