SQL Server Execution Plans

Author: Grant Fritchey
Publisher: Red Gate Books
ISBN: 9781910035245
Category : Computers
Languages : en
Pages : 520

Book Description
If a query is performing poorly, and you can't understand why, then that query's execution plan will tell you not only what data set is coming back, but also what SQL Server did, and in what order, to get that data. It will reveal how the data was retrieved, and from which tables and indexes, what types of joins were used, at what point filtering, sorting and aggregation occurred, and a whole lot more. These details will often highlight the likely source of any problem. I wrote this book with the singular goal of teaching you how to read SQL Server Execution plans It will explain, among many other things, the following: How to capture execution plans using manual and automatic methods A documented method for reading and interpreting execution plans How common SQL Server objects, such as indexes, views, stored procedures, and so on, appear in execution plans How to control execution plans with hints and plan guides, and why this is a double-edged sword How the Query Store works with, and collects data on, execution plans With this knowledge, you'll have everything you need to read the execution plan, for any query of your own, regardless of complexity, and understand what it does and what is causing the bad performance. It is still your job to work out how best to fix it, but your new understanding of execution plans will give a much better chance of success!

SQL Server Execution Plans

Author: Grant Fritchey
Publisher: Red Gate Books
ISBN: 9781906434939
Category : Computers
Languages : en
Pages : 344

Book Description
Every day, out in the various online forums devoted to SQL Server, and on Twitter, the same types of questions come up repeatedly: Why is this query running slowly? Why is SQL Server ignoring my index? Why does this query run quickly sometimes and slowly at others? My response is the same in each case: have you looked at the execution plan? An execution plan describes what's going on behind the scenes when SQL Server executes a query. It shows how the query optimizer joined the data from the various tables defined in the query, which indexes it used, if any, how it performed any aggregations or sorting, and much more. It also estimates the cost of all of these operations, in terms of the relative load placed on the system. Every Database Administrator, developer, report writer, and anyone else who writes T-SQL to access SQL Server data, must understand how to read and interpret execution plans.My book leads you right from the basics of capturing plans, through how to interrupt them in their various forms, graphical or XML, and then how to use the information you find there to diagnose the most common causes of poor query performance, and so optimize your SQL queries, and improve your indexing strategy.

The Art of High Performance SQL Code

Author: Grant Fritchey
Publisher:
ISBN: 9781906434021
Category : Computers
Languages : en
Pages : 242

Book Description
Execution plans show you what's going on behind the scenes in SQL Server. They can provide you with a wealth of information on how your queries are being executed by SQL Server, including: Which indexes are being used, and where no indexes are being used at all. How the data is being retrieved, and joined, from the tables defi ned in your query. How aggregations in GROUP BY queries are put together. The anticipated load and the estimated cost that all these operations place upon the system. Grant Fritchey's book is the only in-depth look at how to improve your SQL query performance through careful design of execution plans. Sample chapters of the ebook have garnered stunning reviews, such as: "All I can say is WOW. This has to be the best reference I have ever seen on Execution Plans in SQL Server. My hats off to Grant Fritchey" Jonathan Kehayias.

SQL Server Execution Plans, 2nd Edition

Author: Grant Fritchey
Publisher:
ISBN:
Category : Database management
Languages : en
Pages : 344

Book Description
Every day the same types of questions come up repeatedly: Why is this query running slowly? Why is SQL Server ignoring my index? My response is the same in each case: have you looked at the execution plan? An execution plan describes what's going on behind the scenes when SQL Server executes a query. It shows how the query optimizer joined the data from the various tables defined in the query, which indexes it used, if any, how it performed any aggregations or sorting, and much more. It also estimates the cost of all of these operations, in terms of the relative load placed on the system. Every Database Administrator, developer, report writer, and anyone else who writes T-SQL to access SQL Server data, must understand how to read and interpret execution plans. My book leads you right from the basics of capturing plans, through how to interrupt them in their various forms, graphical or XML, and then how to use the information you find there to diagnose the most common causes of poor query performance, and so optimize your SQL queries, and improve your indexing strategy.

SQL Tuning

Author: Dan Tow
Publisher: "O'Reilly Media, Inc."
ISBN: 059655236X
Category : Computers
Languages : en
Pages : 338

Book Description
A poorly performing database application not only costs users time, but also has an impact on other applications running on the same computer or the same network. SQL Tuning provides an essential next step for SQL developers and database administrators who want to extend their SQL tuning expertise and get the most from their database applications.There are two basic issues to focus on when tuning SQL: how to find and interpret the execution plan of an SQL statement and how to change SQL to get a specific alternate execution plan. SQL Tuning provides answers to these questions and addresses a third issue that's even more important: how to find the optimal execution plan for the query to use.Author Dan Tow outlines a timesaving method he's developed for finding the optimum execution plan--rapidly and systematically--regardless of the complexity of the SQL or the database platform being used. You'll learn how to understand and control SQL execution plans and how to diagram SQL queries to deduce the best execution plan for a query. Key chapters in the book include exercises to reinforce the concepts you've learned. SQL Tuning concludes by addressing special concerns and unique solutions to "unsolvable problems."Whether you are a programmer who develops SQL-based applications or a database administrator or other who troubleshoots poorly tuned applications, SQL Tuning will arm you with a reliable and deterministic method for tuning your SQL queries to gain optimal performance.

Mastering SQL Server Profiler

Author: Brad McGehee
Publisher: Red Gate Software
ISBN: 1906434115
Category : Client/server computing
Languages : en
Pages : 306

Book Description

Learning SQL

Author: Alan Beaulieu
Publisher: O'Reilly Media
ISBN: 059655107X
Category : Computers
Languages : en
Pages : 338

Book Description
Updated for the latest database management systems -- including MySQL 6.0, Oracle 11g, and Microsoft's SQL Server 2008 -- this introductory guide will get you up and running with SQL quickly. Whether you need to write database applications, perform administrative tasks, or generate reports, Learning SQL, Second Edition, will help you easily master all the SQL fundamentals. Each chapter presents a self-contained lesson on a key SQL concept or technique, with numerous illustrations and annotated examples. Exercises at the end of each chapter let you practice the skills you learn. With this book, you will: Move quickly through SQL basics and learn several advanced features Use SQL data statements to generate, manipulate, and retrieve data Create database objects, such as tables, indexes, and constraints, using SQL schema statements Learn how data sets interact with queries, and understand the importance of subqueries Convert and manipulate data with SQL's built-in functions, and use conditional logic in data statements Knowledge of SQL is a must for interacting with data. With Learning SQL, you'll quickly learn how to put the power and flexibility of this language to work.

Performance Tuning with SQL Server Dynamic Management Views

Author: Louis Davidson
Publisher: Fastprint Publishing
ISBN: 9781906434472
Category : Computers
Languages : en
Pages : 344

Book Description
Dynamic Management Views (DMVs) are a significant and valuable addition to the DBA's troubleshooting armory, laying bare previously unavailable information regarding the under-the-covers activity of your database sessions and transactions. Why, then, aren't all DBAs using them? Why do many DBAs continue to ignore them in favour of "tried and trusted" tools such as sp_who2, DBCC OPENTRAN, and so on, or make do with the "ready made" reports built into SSMS? Why do even those that do use the DMVs speak wistfully about "good old sysprocesses"? There seem to be two main factors at work. Firstly, some DBAs are simply unaware of the depth and breadth of the information that is available from the DMvs, or how it might help them troubleshoot common issues. This book investigates all of the DMVs that are most frequently useful to the DBA in investigating query execution, index usage, session and transaction activity, disk IO, and how SQL Server is using or abusing the operating system. Secondly, the DMVs have a reputation of being difficult to use. In the process of exposing as much useful data as possible, sysprocesses has been de-normalized, and many new views and columns have been added. This fact, coupled with the initially-baffling choices of what columns will be exposed where, has lead to some DBAs to liken querying DMVs to "collecting mystic spells." In fact, however, once you start to write your own scripts, you'll see the same tricks, and similar join patterns, being used time and again. As such, a relatively small core set of scripts can be readily adapted to suit any requirement. This book is here to de-mystify the process of collecting the information you need to troubleshoot SQL Server problems. It will highlight the core techniques and "patterns" that you need to master, and will provide a core set of scripts that you can use and adapt for your own systems, including how to: * Root out the queries that are causing memory or CPU pressure on your system * Investigate caching, and query plan reuse * Identify index usage patterns * Track fragmentation in clustered indexes and heaps * Get full details on blocking and blocked transactions, including the exact commands being executed, and by whom. * Find out where SQL Server is spending time waiting for resources to be released, before proceeding * Monitor usage and growth of tempdb The DMVs don't make existing, built-in, performance tools obsolete. On the contrary, they complement these tools, and offer a flexibility, richness and granularity that are simply not available elsewhere. Furthermore, you don't need to master a new GUI, or a new language in order to use them; it's all done in a language all DBAs know and mostly love: T-SQL.

SQL Server Query Performance Tuning

Author: Grant Fritchey
Publisher: Apress
ISBN: 1430267429
Category : Computers
Languages : en
Pages : 593

Book Description
Queries not running fast enough? Wondering about the in-memory database features in 2014? Tired of phone calls from frustrated users? Grant Fritchey’s book SQL Server Query Performance Tuning is the answer to your SQL Server query performance problems. The book is revised to cover the very latest in performance optimization features and techniques, especially including the newly-added, in-memory database features formerly known under the code name Project Hekaton. This book provides the tools you need to approach your queries with performance in mind. SQL Server Query Performance Tuning leads you through understanding the causes of poor performance, how to identify them, and how to fix them. You’ll learn to be proactive in establishing performance baselines using tools like Performance Monitor and Extended Events. You’ll learn to recognize bottlenecks and defuse them before the phone rings. You’ll learn some quick solutions too, but emphasis is on designing for performance and getting it right, and upon heading off trouble before it occurs. Delight your users. Silence that ringing phone. Put the principles and lessons from SQL Server Query Performance Tuning into practice today. Covers the in-memory features from Project Hekaton Helps establish performance baselines and monitor against them Guides in troubleshooting and eliminating of bottlenecks that frustrate users

SQL Server 2017 Query Performance Tuning

Author: Grant Fritchey
Publisher: Apress
ISBN: 1484238885
Category : Computers
Languages : en
Pages : 947

Book Description
Identify and fix causes of poor performance. You will learn Query Store, adaptive execution plans, and automated tuning on the Microsoft Azure SQL Database platform. Anyone responsible for writing or creating T-SQL queries will find valuable the insight into bottlenecks, including how to recognize them and eliminate them. This book covers the latest in performance optimization features and techniques and is current with SQL Server 2017. If your queries are not running fast enough and you’re tired of phone calls from frustrated users, then this book is the answer to your performance problems. SQL Server 2017 Query Performance Tuning is about more than quick tips and fixes. You’ll learn to be proactive in establishing performance baselines using tools such as Performance Monitor and Extended Events. You’ll recognize bottlenecks and defuse them before the phone rings. You’ll learn some quick solutions too, but emphasis is on designing for performance and getting it right. The goal is to head off trouble before it occurs. What You'll Learn Use Query Store to understand and easily change query performance Recognize and eliminate bottlenecks leading to slow performance Deploy quick fixes when needed, following up with long-term solutions Implement best practices in T-SQL to minimize performance risk Design in the performance that you need through careful query and index design Utilize the latest performance optimization features in SQL Server 2017 Protect query performance during upgrades to the newer versions of SQL Server Who This Book Is For Developers and database administrators with responsibility for application performance in SQL Server environments. Anyone responsible for writing or creating T-SQL queries will find valuable the insight into bottlenecks, including how to recognize them and eliminate them.