Introduction

Abstract

Concurrency and locking are some of the most complex topics when it comes to databases. A query that usually executes fast and without problems may suddenly take much longer or fail with an error when the conditions are “just right,” so locking or contention becomes a problem. You may ask yourself why locks are around when they can cause such problems. This and the next 11 chapters will try to explain that as well as how you best deal with them. The last six chapters of the book go through six case studies putting the information together in realistic scenarios together with analysis and how to avoid or reduce the issue.