Understanding Locking, Data Modification and Committing Data in SQL Server

Learn about how SQL Server uses locks when modifying data and how data is committed to a database after data changes.

Optimized Locking

Transaction locking and row versioning guide

In any database, mismanagement of transactions often leads to contention and performance problems in systems that have many users. As the number of users that access the data increases, it becomes important to have applications that use transactions efficiently. This guide describes the locking and row versioning mechanisms the SQL Server Database Engine uses to ensure the physical integrity of each transaction and provides information on how applications can control transactions efficiently.

The Lock Escalation Threshold – Part 1

This article isn’t about the act of lock escalation itself, which is already well documented and generally well understood. Some myths (like row locks escalating to page locks) persist, but challenging those yet again probably wouldn’t change much.

The Update Lock

Reseed Locks

Lock Scenarios Using sys.dm_tran_locks

Learn about the impact of locking and blocking in sessions through some demonstrations of different types of actions.

SELECT Queries and Type of Locking

Transaction Locking and Row Versioning Guide

This guide describes the locking and row versioning mechanisms the SQL Server Database Engine uses to ensure the physical integrity of each transaction and provides information on how applications can control transactions efficiently.

Lock Owner Blocks