03 April 2009
03 April 2009

Finding the causes of poor performance in SQL Server, Part 2

In the first part of this series of articles, Gail showed how to find the procedures that contributed most to performance problems. In this final part, she shows how to use query statistics to pinpoint the queries that are causing the biggest problems, and then use the query execution plans to find out which operations are the root cause. With this information one can select and modify the indexes that can optimize the plans and therefore performance of the query.… Read more
09 March 2009
09 March 2009

Finding the Causes of Poor Performance in SQL Server, Part 1

To tackle performance problems with applications, you first find the queries that constitute a typical workload, using SQL Profiler: Then, from the trace, you find the queries or stored procedures that are having the most impact. After that, it is down to examining the execution plans and query statistics to identify queries that need tuning and indexes that need creating. You then See what effects you've had and maybe repeat the process. Gail explains all, in a two-part article.… Read more
26 February 2009
26 February 2009

Understanding More Complex Query Plans

In order to be able to tackle performance issues in SQL Server , and write effective SQL, it is essential to gain a sound understanding of execution plans. Grant's previous article described graphical execution plans for Simple SQL queries. He now moves on to cover some of the more complicated plans that every database programmer will see.… Read more
03 February 2009
03 February 2009

How to Identify Slow Running Queries with SQL Profiler

With SQL Server Profiler, it is easy to discover all those queries that are running slowly. Once poorly performing queries are identified, there comes the harder task of speeding them up. Once again, the Profiler can provide a lot of information that can help diagnose and resolve these performance problems. Brad describes this essential part of the process of performance-tuning in an article taken from a chapter to his new book, Mastering SQL Server Profiler.… Read more
24 July 2008
24 July 2008

Investigating SQL Server 2008 Wait Events with XEVENTS

Some reasons for the slow-running of database applications aren't obvious. Occasionally, even the profiler won't tell you enough to remedy a problem, especially when a SQL Statement is being forced to wait. Now, in SQL Server 2008, come XEvents, which allow you to look at those wait events that are slowing your SQL Statements. Mario Broodbakker continues his series about SQL Server Wait Events SQL Server 2008 wait event based performance analysis using XEvents… Read more
11 May 2008
11 May 2008

Execution Plan Basics

Every day, out in the various discussion boards devoted to Microsoft SQL Server, the same types of questions come up again and again: Why is this query running slow? Is my index getting used? Why isn't my index getting used? Why does this query run faster than this query?. The correct response is probably different in each case, but in order to arrive at the answer you have to ask the same return question in each case: have you looked at the execution plan? … Read more
22 March 2007
22 March 2007

SQL Server Wait Events: Taking the Guesswork out of Performance Profiling

Measuring what is actually happening is always the best course of action when investigating performance issues on databases, rather than relying on cache hit ratios, or best practices, or worst of all, guesswork. This article introduces some techniques that will allow you to pinpoint exactly where the performance issues are in your system, so you'll know exactly where to spend your time (and money) in solving them. … Read more