On the other hand, if you're not well versed in the theory, you can fall into several traps. In SQL and Relational Theory, author C.J. Date demonstrates how you can apply relational theory directly to your use of SQL. With numerous examples and clear explanations of the reasoning behind them, you'll learn how to deal with common SQL dilemmas, such as:Should database access granted be through views instead of base tables? Nulls in your database are causing you to get wrong answers. Why? What can you do about it? Could you write an SQL query to find employees who have never been in the same department for more than six months at a time? SQL supports "quantified comparisons," but they're better avoided. Why? How do you avoid them? Constraints are crucially important, but most SQL products don't support them properly. What can you do to resolve this situation? Database theory and practice have evolved since Edgar Codd originally defined the relational model back in 1969. Independent of any SQL products, SQL and Relational Theory draws on decades of research to present the most up-to-date treatment of the material available anywhere. Anyone with a modest to advanced background in SQL will benefit from the many insights in this book.

    The book begins by introducing the unique features and concepts of Go. Then, you'll get hands-on experience writing real-world applications including websites and network servers, as well as techniques to manipulate and convert data at speeds that will make your friends jealous.

    Lambda enables users to develop code that executes in response to events - API calls, file uploads, schedules, etc - and upload it without worrying about managing traditional server metrics such as disk space, memory, or CPU usage. With its "per execution" cost model, Lambda can enable organizations to save hundreds or thousands of dollars on computing costs. With in-depth walkthroughs, large screenshots, and complete code samples, the reader is guided through the step-by-step process of creating new functions, responding to infrastructure events, developing API backends, executing code at specified intervals, and much more. Introduction to AWS Computing Evolution of the Computing Workload Lambda Background The Internals The Basics Functions Languages Resource Allocation Getting Set Up Hello World Uploading the Function Working with Events AWS Events Custom Events The Context Object Properties Methods Roles and Permissions Policies Trust Relationships Console Popups Cross Account Access Dependencies and Resources Node Modules OS Dependencies OS Resources OS Commands Logging Searching Logs Testing Your Function Lambda Console Tests Third-Party Testing Libraries Simulating Context Hello S3 Object The Bucket The Role The Code The Event The Trigger Testing When Lambda Isn’t the Answer Host Access Fine-Tuned Configuration Security Long-Running Tasks Where Lambda Excels AWS Event-Driven Tasks Scheduled Events (Cron) Offloading Heavy Processing API Endpoints Infrequently Used Services Real-World Use Cases S3 Image Processing Shutting Down Untagged Instances Triggering CodeDeploy with New S3 Uploads Processing Inbound Email Enforcing Security Policies Detecting Expiring Certificates Utilizing the AWS API Execution Environment The Code Pipeline Cold vs. Hot Execution What is Saved in Memory Scaling and Container Reuse From Development to Deployment Application Design Development Patterns Testing Deployment Monitoring Versioning and Aliasing Costs Short Executions Long-Running Processes High-Memory Applications Free Tier Calculating Pricing CloudFormation Reusable Template with Minimum Permissions Cross Account Access CloudWatch Alerts AWS API Gateway API Gateway Event Creating the Lambda Function Creating a New API, Resource, and Method Initial Configuration Mapping Templates Adding a Query String Using HTTP Request Information Within Lambda Deploying the API Additional Use Cases Lambda Competitors Iron.io StackHut WebTask.io Existing Cloud Providers The Future of Lambda More Resources Conclusion

    With countless satisfied developers, tens of thousands of freely available libraries, and continual improvements to the language and its ecosystem, modern Perl development can be easy, reliable, and fun. To take advantage of the full power of Perl 5--to become a true expert, capable of solving any problem put before you--you must understand the language. Modern Perl explains Perl 5 from theory to implementation, including Perl 5.12.

    In this revision, the author takes a structured approach to explaining how networks function.

    It supports secure remote logins, secure file transfer between computers, and a unique "tunneling" capability that adds encryption to otherwise insecure network applications. Best of all, SSH is free, with feature-filled commercial versions available as well.SSH: The Secure Shell: The Definitive Guide covers the Secure Shell in detail for both system administrators and end users. It demystifies the SSH man pages and includes thorough coverage of:SSH1, SSH2, OpenSSH, and F-Secure SSH for Unix, plus Windows and Macintosh products: the basics, the internals, and complex applications.Configuring SSH servers and clients, both system-wide and per user, with recommended settings to maximize security.Advanced key management using agents, agent forwarding, and forced commands.Forwarding (tunneling) of TCP and X11 applications in depth, even in the presence of firewalls and network address translation (NAT).Undocumented behaviors of popular SSH implementations.Installing and maintaining SSH systems.Whether you're communicating on a small LAN or across the Internet, SSH can ship your data from "here" to "there" efficiently and securely. So throw away those insecure .rhosts and hosts.equiv files, move up to SSH, and make your network a safe place to live and work.

    This practical "how-to" handbook, written by experienced programmer Hal Fulton, has been updated to not only explain the newest features of Ruby, but also to show how people use Ruby today, including coverage of Ruby on Rails.

    In this book, author Gojko Adzic distills interviews with successful teams worldwide, sharing how they specify, develop, and deliver software, without defects, in short iterative delivery cycles.About the Technology Specification by Example is a collaborative method for specifying requirements and tests. Seven patterns, fully explored in this book, are key to making the method effective. The method has four main benefits: it produces living, reliable documentation; it defines expectations clearly and makes validation efficient; it reduces rework; and, above all, it assures delivery teams and business stakeholders that the software that's built is right for its purpose.About the Book This book distills from the experience of leading teams worldwide effective ways to specify, test, and deliver software in short, iterative delivery cycles. Case studies in this book range from small web startups to large financial institutions, working in many processes including XP, Scrum, and Kanban.This book is written for developers, testers, analysts, and business people working together to build great software.Purchase of the print book comes with an offer of a free PDF, ePub, and Kindle eBook from Manning. Also available is all code from the book.What's InsideCommon process patterns How to avoid bad practices Fitting SBE in your process 50+ case studies For additional resources go to specificationbyexample.com.

    Sipser's candid, crystal-clear style allows students at every level to understand and enjoy this field. His innovative "proof idea" sections explain profound concepts in plain English. The new edition incorporates many improvements students and professors have suggested over the years, and offers updated, classroom-tested problem sets at the end of each chapter.

    With the king and queen away, she has to manage the Kingdom of Kod's humongous fruit-selling empire. Overseas departments, scads of inventory, conflicting prices, and so many customers! It's all such a confusing mess. But a mysterious book and a helpful fairy promise to solve her organizational problems-with the practical magic of databases.In The Manga Guide to Databases, Tico the fairy teaches the Princess how to simplify her data management. We follow along as they design a relational database, understand the entity-relationship model, perform basic database operations, and delve into more advanced topics. Once the Princess is familiar with transactions and basic SQL statements, she can keep her data timely and accurate for the entire kingdom. Finally, Tico explains ways to make the database more efficient and secure, and they discuss methods for concurrency and replication.Examples and exercises (with answer keys) help you learn, and an appendix of frequently used SQL statements gives the tools you need to create and maintain full-featured databases.(Of course, it wouldn't be a royal kingdom without some drama, so read on to find out who gets the girl-the arrogant prince or the humble servant.)This EduManga book is a translation of a bestselling series in Japan, co-published with Ohmsha, Ltd., of Tokyo, Japan.

    The leading selling UNIX internals book on the market.

    The Hacker Playbook provides them their own game plans. Written by a longtime security professional and CEO of Secure Planet, LLC, this step-by-step guide to the “game” of penetration hacking features hands-on examples and helpful advice from the top of the field.Through a series of football-style “plays,” this straightforward guide gets to the root of many of the roadblocks people may face while penetration testing—including attacking different types of networks, pivoting through security controls, privilege escalation, and evading antivirus software.From “Pregame” research to “The Drive” and “The Lateral Pass,” the practical plays listed can be read in order or referenced as needed. Either way, the valuable advice within will put you in the mindset of a penetration tester of a Fortune 500 company, regardless of your career or level of experience.This second version of The Hacker Playbook takes all the best "plays" from the original book and incorporates the latest attacks, tools, and lessons learned. Double the content compared to its predecessor, this guide further outlines building a lab, walks through test cases for attacks, and provides more customized code.Whether you’re downing energy drinks while desperately looking for an exploit, or preparing for an exciting new job in IT security, this guide is an essential part of any ethical hacker’s library—so there’s no reason not to get in the game.

    As traffic volume and data demands increase, these applications become more complicated and brittle, exposing risks and compromising availability. This practical guide shows IT, devops, and system reliability managers how to prevent an application from becoming slow, inconsistent, or downright unavailable as it grows.Scaling isn't just about handling more users; it's also about managing risk and ensuring availability. Author Lee Atchison provides basic techniques for building applications that can handle huge quantities of traffic, data, and demand without affecting the quality your customers expect.In five parts, this book explores:Availability: learn techniques for building highly available applications, and for tracking and improving availability going forwardRisk management: identify, mitigate, and manage risks in your application, test your recovery/disaster plans, and build out systems that contain fewer risksServices and microservices: understand the value of services for building complicated applications that need to operate at higher scaleScaling applications: assign services to specific teams, label the criticalness of each service, and devise failure scenarios and recovery plansCloud services: understand the structure of cloud-based services, resource allocation, and service distribution

    It brings together all the knowledge needed to write any program, use any standard or third-party Python 3 library, and create new library modules of your own.

    Over the past five years, authors Dustin Boswell and Trevor Foucher have analyzed hundreds of examples of "bad code" (much of it their own) to determine why they’re bad and how they could be improved. Their conclusion? You need to write code that minimizes the time it would take someone else to understand it—even if that someone else is you.This book focuses on basic principles and practical techniques you can apply every time you write code. Using easy-to-digest code examples from different languages, each chapter dives into a different aspect of coding, and demonstrates how you can make your code easy to understand.Simplify naming, commenting, and formatting with tips that apply to every line of codeRefine your program’s loops, logic, and variables to reduce complexity and confusionAttack problems at the function level, such as reorganizing blocks of code to do one task at a timeWrite effective test code that is thorough and concise—as well as readable"Being aware of how the code you create affects those who look at it later is an important part of developing software. The authors did a great job in taking you through the different aspects of this challenge, explaining the details with instructive examples." —Michael Hunger, passionate Software Developer