DB - A Critique of ANSI SQL Isolation Levels

DB - A Critique of ANSI SQL Isolation Levels.pdf ANSI SQL-92 [MS, ANSI] defines Isolation Levels in terms of phenomena: Dirty Reads, Non-Re-peatable Reads, and Phantoms. This document shows that these phenomena and the ANSI SQL definitions fail to characterize several popular isolation levels, including the standard locking implementations of the levels. Investigating the ambiguities of the phenomena leads to clearer definitions.