In this sample chapter from Exam Ref 70-762 Developing SQL Databases, explore skills related to the goal of managing database concurrency, including how to implement transactions, manage isolation levels, and more.
In a typical environment, a database receives multiple requests to perform an operation and often these requests can occur concurrently. As an administrator, you must understand how SQL Server handles these requests by default and the available options for changing this default behavior. Your overarching goal is to prevent unexpected results, while enabling as many processes as possible.
The 70-762 exam tests your skills related to this goal of managing database concurrency. Here in Skill 3.1, we review the basic properties and behaviors of transactions in SQL Server and the role of transactions in high-concurrency databases. Skill 3.2 addresses the available options for managing concurrency in SQL Server by using isolation levels and explores in detail the differences between isolation levels as well as the effect each isolation level has on concurrent transactions, system resources, and overall performance. Then in Skill 3.3 we explore the tools at your disposal to better understand locking behavior in SQL Server and the steps you can take to remediate deadlocks. Skill 3.4 introduces memory-optimized tables as another option for improving concurrency by explaining the use cases for which this approach is best, how to optimize performance when tables are held in memory instead of on disk, and considerations for using and analyzing performance of natively compiled stored procedures.
Skills in this chapter:
Manage isolation levels
Optimize concurrency and locking behavior
Implement memory-optimized tables and native stored procedures