Introducing SQL Server

Transcription

1 Introducing SQL Server Mike McQuillan

2 Introducing SQL Server Copyright 2015 by Mike McQuillan This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. Exempted from this legal reservation are brief excerpts in connection with reviews or scholarly analysis or material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Duplication of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher s location, in its current version, and permission for use must always be obtained from Springer. Permissions for use may be obtained through RightsLink at the Copyright Clearance Center. Violations are liable to prosecution under the respective Copyright Law. ISBN-13 (pbk): ISBN-13 (electronic): Trademarked names, logos, and images may appear in this book. Rather than use a trademark symbol with every occurrence of a trademarked name, logo, or image we use the names, logos, and images only in an editorial fashion and to the benefit of the trademark owner, with no intention of infringement of the trademark. The use in this publication of trade names, trademarks, service marks, and similar terms, even if they are not identified as such, is not to be taken as an expression of opinion as to whether or not they are subject to proprietary rights. While the advice and information in this book are believed to be true and accurate at the date of publication, neither the authors nor the editors nor the publisher can accept any legal responsibility for any errors or omissions that may be made. The publisher makes no warranty, express or implied, with respect to the material contained herein. Managing Director: Welmoed Spahr Lead Editor: Jonathan Gennick Technical Reviewer: Bradley Beard Editorial Board: Steve Anglin, Mark Beckner, Gary Cornell, Louise Corrigan, Jim DeWolf, Jonathan Gennick, Robert Hutchinson, Michelle Lowman, James Markham, Susan McDermott, Matthew Moodie, Jeffrey Pepper, Douglas Pundick, Ben Renow-Clarke, Gwenan Spearing, Matt Wade, Steve Weiss Coordinating Editor: Jill Balzano Copy Editor: James Fraleigh Compositor: SPi Global Indexer: SPi Global Artist: SPi Global Cover Designer: Anna Ishchenko Distributed to the book trade worldwide by Springer Science+Business Media New York, 233 Spring Street, 6th Floor, New York, NY Phone SPRINGER, fax (201) , orders-ny@springer-sbm.com, or visit Apress Media, LLC is a California LLC and the sole member (owner) is Springer Science + Business Media Finance Inc (SSBM Finance Inc). SSBM Finance Inc is a Delaware corporation. For information on translations, please rights@apress.com, or visit Apress and friends of ED books may be purchased in bulk for academic, corporate, or promotional use. ebook versions and licenses are also available for most titles. For more information, reference our Special Bulk Sales ebook Licensing web page at Any source code or other supplementary material referenced by the author in this text is available to readers at For detailed information about how to locate your book s source code, go to

3 For Jo & Grace, thank you for supporting me.

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5 Contents at a Glance About the Author...xix About the Technical Reviewer...xxi Acknowledgments...xxiii Chapter 1: What Is SQL Server?... 1 Chapter 2: Obtaining and Installing SQL Server... 7 Chapter 3: Database Basics Chapter 4: Tables Chapter 5: Putting Good Tables Together Chapter 6: Automating Deployment with SQLCMD Chapter 7: NULLs and Table Constraints Chapter 8: DML (or Inserts, Updates, and Deletes) Chapter 9: Bulk Inserting Data Chapter 10: Creating Data Import Scripts Chapter 11: The SELECT Statement Chapter 12: Joining Tables Chapter 13: Views Chapter 14: Indexes Chapter 15: Transactions Chapter 16: Functions v

6 Contents at a Glance Chapter 17: Table-Valued Functions Chapter 18: Stored Procedures Part Chapter 19: Stored Procedures Part Chapter 20: Bits and Pieces Appendix A: SQL Data Types Appendix B: Glossary Appendix C: Common SQL Server System Objects Appendix D: Exercises Index vi

7 Contents About the Author...xix About the Technical Reviewer...xxi Acknowledgments...xxiii Chapter 1: What Is SQL Server?... 1 A Quick History of SQL Server... 1 SQL Server Services... 2 Business Intelligence Services... 3 Editions of SQL Server... 4 SQL Server Tools and Utilities... 4 Time to Kick Off... 5 Chapter 2: Obtaining and Installing SQL Server... 7 Downloading SQL Server Express... 7 Beginning Installation... 8 Installation Wizard Steps Updates and Features Instance Features Shared Features Database Instances Default Instances Named Instances The Instance Configuration Page Service Accounts vii

8 Contents Collation Database Engine Configuration Server Configuration Data Directories User Instances FILESTREAM Reporting Services Configuration Installing A Very Quick SSMS Overview Summary Chapter 3: Database Basics What Is a Database? Types of Databases System Databases User Databases Creating a Database Using SSMS Dropping a Database Using SSMS Creating a Database Using T-SQL Dropping A Database Using T-SQL Advanced Database Scripting Creating Scripts Automatically Database Properties Summary Chapter 4: Tables Table Basics A Starting Point Naming Tables Types Of Table viii

9 Contents Columns and Table Data Types Primary Keys Clustered and Nonclustered Keys Foreign Keys and Relationships IDENTITY Columns Summary Chapter 5: Putting Good Tables Together Database Normalization First Normal Form Multiple-Column Repeating Groups Second Normal Form Third Normal Form Further Analysis Looking Things Over A Second Enhancement Summary Chapter 6: Automating Deployment with SQLCMD What Is SQLCMD? Why We Need a SQLCMD Script Rollback Scripts Creating the SQLCMD Rollback Script Creating the SQLCMD Apply Script Summary Chapter 7: NULLs and Table Constraints NULL Constraints Constraints Default Constraints Creating a Default Constraint Table Constraints Part 1 Check Constraints ix

10 Contents Creating a Table Constraint Creating a Column Constraint Table Constraints Part 2 Unique Constraints Some Constraints Are Really Indexes Summary Chapter 8: DML (or Inserts, Updates, and Deletes) Reference Data vs. Real Data Inserting Data More Inserts The UPDATE Statement Deleting Records Summary Chapter 9: Bulk Inserting Data The BULK INSERT Statement Preparing the Data File Importing the Data File More Bulk Insert Escapades Truncating Tables Summary Chapter 10: Creating Data Import Scripts Purpose of the Import Script Starting the Script with Variables Reference Data Lookups Inserting the Contact Record Adding Subrecords Displaying the Outcome The Rollback Script Summary x

11 Contents Chapter 11: The SELECT Statement What Is the SELECT Statement For? The Simple SELECT Statement The WHERE Clause The AND Operator The OR Operator The IN Operator Mixing Operators Ordering Data Grouping Data Column Aliases Limiting Rows with TOP Merging Columns Summary Chapter 12: Joining Tables INNER JOIN LEFT OUTER JOIN RIGHT OUTER JOIN FULL OUTER JOIN CROSS JOIN Using JOINs In DML Statements Summary Chapter 13: Views What Are Views For? Creating Views Adding Columns to Views Checking If a View Already Exists Broken Views SCHEMABINDING xi

12 Contents xii Using Views in Joins Using Views in Other Views Indexed Views Dropping the Views Summary Chapter 14: Indexes What Is an Index? Why Are Indexes Useful? What Do Indexes Affect? Identifying Which Columns to Index How Indexes Work Table Scans B-Trees Non-Clustered Indexes And B-Trees Basics Of The CREATE INDEX Statement Clustered Indexes Creating a Clustered Index Modifying an Index Using SSMS Checking If an Index Exists with T-SQL Non-Clustered Indexes Execution Plan Percentages Execution Plans: A Quick Summary Indexed Columns vs. Included Columns Filtered Indexes Unique Indexes Other Types of Index Maintaining Indexes Identifying Index Fragmentation Altering Indexes Disabling Indexes

13 Contents Rebuilding Indexes Reorganizing Indexes Altering Indexes Using SSMS Dropping Indexes Statistics Creating Indexed Views Are Indexes Ever a Bad Idea? Summary Chapter 15: Transactions What Is a Transaction? ACID A Transaction Example T-SQL Transaction Statements BEGIN TRANSACTION COMMIT TRANSACTION ROLLBACK TRANSACTION When Should I Use Transactions? What If I Don t Use Transactions? Creating a Transaction Locking a Table with a Bad Transaction sp_who Rolling Back the Bad Transaction Committing Transactions Rolling Back Transactions General Transaction Rules Keep Transactions Short Limit Transactions to DML Statements Don t Be Afraid to Split Transactions Up Summary xiii

14 Contents Chapter 16: Functions xiv Function Types Deterministic vs. Non-Deterministic Functions User-Defined Functions vs. System Functions Why Are Functions Useful? What Can t I Do with A Function? A First Function The CREATE FUNCTION Statement A Scalar Function: ContactName Testing Our Function Side Effects Further Testing Dropping Functions Saving the Function Using the Function in Queries Summary Chapter 17: Table-Valued Functions Why TVFs Are Cool Sometimes, TVFs Are Not So Cool Building a TVF Adding the Script to SQLCMD Creating the Rollback Script Using TVFs in Queries Calling a TVF Joining to a TVF The APPLY Operator CROSS APPLY OUTER APPLY Performance Issues Summary

15 Contents Chapter 18: Stored Procedures Part What Are Stored Procedures, and Why Should I Use Them? CREATE PROCEDURE and ALTER PROCEDURE DROP PROCEDURE SSMS and Stored Procedures A First Stored Procedure Executing a Stored Procedure SET NOCOUNT ON and OFF Schema Names Returning Data from Stored Procedures Parameters Input Parameters Default Parameter Values Output Parameters READONLY Parameters Basic Debugging with PRINT Rollback Summary Chapter 19: Stored Procedures Part Enhancing the InsertContact Stored Procedure User-Defined Types Why Use Them? Creating a UDT Rolling Back the UDT Using the UDT Adding a Custom Type to a Stored Procedure Executing the Stored Procedure Set-Based Logic Summary xv

16 Contents Chapter 20: Bits and Pieces Security GRANT, DENY, and REVOKE Built-in Security Roles Fixed Server Roles Fixed Database Roles Schemas Triggers Profiler and Extended Events SQL Server Profiler Starting Profiler Extended Events Summary Appendix A: SQL Data Types Appendix B: Glossary Appendix C: Common SQL Server System Objects Global Variables System Functions AVG( ) COALESCE(value1, value2, valuen) COUNT(criteria) DATABASEPROPERTYEX(database name, property name) DATEADD(datepart, number to add/subtract, date) DAY(date) DB_ID( ) xvi

17 Contents DB_NAME(id) GETDATE( ) GETUTCDATE( ) LEFT(string, number of characters) LEN(string) LOWER(string) LTRIM(string) MAX( ) MIN( ) MONTH(date) OBJECT_NAME(id) RIGHT(string, number of characters) RTRIM(string) SCOPE_IDENTITY( ) UPPER(string) YEAR(date) System Stored Procedures sp_help 380 Appendix D: Exercises Index xvii

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19 About the Author Mike McQuillan is a software and database specialist who lives with his wife and daughter in the United Kingdom. Mike is a polyglot programmer who began messing around with computers in the 1980s, first with an Atari 800XL and then a Sinclair Spectrum. He took up databases in the 1990s, and quickly fell in love with SQL. He s been working with SQL Server since version 7, and is an SQL Server MCSA. When he s not tinkering with computers, Mike and his family enjoy lengthy walks around Cheshire with the family pups, Dolly and Bertie (who keep his feet warm when he s writing). xix

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21 About the Technical Reviewer Bradley Beard is a software engineer with more than 15 years experience writing dynamic, interactive websites using ColdFusion and SQL Server. He graduated from Florida Institute of Technology in 2007 with a Master of Science in Computer Information Systems, and studied for his undergraduate degrees in CIS and Technology Management at Herzing University. In 2013, he earned the MCSA: SQL Server 2012 certification from Microsoft. His continual quest for learning has earned him shelves full of books at home and at work, most of which are about SQL Server, ColdFusion, or general web architectures or frameworks. He lives in Palm Bay, Florida with his wife, Jessica, and children, Josh, Kaylee, Matthew, and Emma. He also apparently runs an animal shelter made up of his dogs, Lady and Bella, and cats, Spice, Simba, Mercury, and Dobby. In his free time, he enjoys fishing and spending time with his wife and kids. Bradley is available for consultation and third-shift remote employment on ColdFusion and SQL Server by contacting bradley.beard@gmail.com. xxi

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23 Acknowledgments Writing a book is a big undertaking, and I wouldn t have managed it without the support of my wonderful wife, Jo, and darling daughter, Grace. I love you both very much. I d also like to thank my parents and the rest of my family and friends just for being around life s been a pretty great ride so far and I m sure it will only improve. Bradley Beard deserves a mention for his excellent technical reviewing, and big thanks also go to Jonathan Gennick, Jill Balzano, and James Fraleigh at Apress for their hard work in ensuring this book made it to print. Finally, a big thank-you to you, the reader, for taking the time to purchase and read this book. I hope you enjoy it as much as I enjoyed writing it. xxiii