SQL Server






Row Versioning in SQL Server

Row versioning fundamentally changes how SQL Server handles read operations during write transactions. Instead of blocking, SQL Server can serve a previous version of the row. We enable row versioning in SQL Server by turning on READ_COMMITTED_SNAPSHOT ISOLATION (RCSI). In this post we will demonstrate blocking without row versioning and…



Concurrency: Phantom Reads

A closer look at the Serializable Transaction Isolation Level and how it could prevent Phantom Reads concurrency issues in SQL Server.



Concurrency: Lost Updates

A closer look at the Read Committed Transaction Isolation Level and how it could allow Lost Update concurrency issues in SQL Server.