Match query 是针对多个用例的最常见和最强大的查询。 它是一个全文搜索查询，返回符合指定条件的文档。 match query 可以即兴使用来查询多个选项。在我之前的文章 “开始使用 Elasticsearch （2）” 对它有很多的描述。
Match 查询的格式
让我们首先看看这个片段显示的 match query 的格式：
GET books/_search
{
"query": {
"match": {
"FIELD": "SEARCH TEXT"
}
}
}正如你在代码片段中看到的，匹配查询期望以字段值的形式定义搜索条件。 该字段可以是文档中存在的任何文本字段，其值将被匹配。 该值可以是一个单词或多个单词，可以是大写、小写或驼峰式。
我们也可以将查询的完整形式中的一些附加参数传递给匹配查询。 到目前为止我们讨论的是 match query 的一种简化形式。 以下代码片段提供了完整形式的示例：
GET books/_search
{
"query": {
"match": {
"FIELD": {
"query":"<SEARCH TEXT>",
"<parameter>":"<MY_PARAM>",
}
}
}
}我们可以通过在搜索 URL 中提供以逗号分隔的索引来跨多个索引进行搜索，如下所示：
GET new_books,classics,top_sellers, crime* /_search
{
...
}上述搜索的另外一种方法就是创建一个包含上面所有索引的 index pattern 来进行搜索。可以详见文章 “Elasticsearch：如何把两个索引连在一起”。
如你所见，调用 _search 端点时可以提供任意数量的索引，包括通配符。
注意：如果我们在搜索请求中省略索引（或多个索引），我们将有效地搜索整个索引。 例如，GET _search { ... } 搜索集群中的所有索引。
使用匹配查询进行搜索
我们首先使用 bulk 命令来创建一个叫做 books 的索引：
POST _bulk
{"index":{"_index":"books","_id":"1"}}
{"title": "Core Java Volume I – Fundamentals","author": "Cay S. Horstmann","edition": 11, "synopsis": "Java reference book that offers a detailed explanation of various features of Core Java, including exception handling, interfaces, and lambda expressions. Significant highlights of the book include simple language, conciseness, and detailed examples.","amazon_rating": 4.6,"release_date": "2018-08-27","tags": ["Programming Languages, Java Programming"]}
{"index":{"_index":"books","_id":"2"}}
{"title": "Effective Java","author": "Joshua Bloch", "edition": 3,"synopsis": "A must-have book for every Java programmer and Java aspirant, Effective Java makes up for an excellent complementary read with other Java books or learning material. The book offers 78 best practices to follow for making the code better.", "amazon_rating": 4.7, "release_date": "2017-12-27", "tags": ["Object Oriented Software Design"]}
{"index":{"_index":"books","_id":"3"}}
{"title": "Java: A Beginner’s Guide", "author": "Herbert Schildt","edition": 8,"synopsis": "One of the most comprehensive books for learning Java. The book offers several hands-on exercises as well as a quiz section at the end of every chapter to let the readers self-evaluate their learning.","amazon_rating": 4.2,"release_date": "2018-11-20","tags": ["Software Design & Engineering", "Internet & Web"]}
{"index":{"_index":"books","_id":"4"}}
{"title": "Java - The Complete Reference","author": "Herbert Schildt","edition": 11,"synopsis": "Convenient Java reference book examining essential portions of the Java API library, Java. The book is full of discussions and apt examples to better Java learning.","amazon_rating": 4.4,"release_date": "2019-03-19","tags": ["Software Design & Engineering", "Internet & Web", "Computer Programming Language & Tool"]}
{"index":{"_index":"books","_id":"5"}}
{"title": "Head First Java","author": "Kathy Sierra and Bert Bates","edition":2, "synopsis": "The most important selling points of Head First Java is its simplicity and super-effective real-life analogies that pertain to the Java programming concepts.","amazon_rating": 4.3,"release_date": "2005-02-18","tags": ["IT Certification Exams", "Object-Oriented Software Design","Design Pattern Programming"]}
{"index":{"_index":"books","_id":"6"}}
{"title": "Java Concurrency in Practice","author": "Brian Goetz with Tim Peierls, Joshua Bloch, Joseph Bowbeer, David Holmes, and Doug Lea","edition": 1,"synopsis": "Java Concurrency in Practice is one of the best Java programming books to develop a rich understanding of concurrency and multithreading.","amazon_rating": 4.3,"release_date": "2006-05-09","tags": ["Computer Science Books", "Programming Languages", "Java Programming"]}
{"index":{"_index":"books","_id":"7"}}
{"title": "Test-Driven: TDD and Acceptance TDD for Java Developers","author": "Lasse Koskela","edition": 1,"synopsis": "Test-Driven is an excellent book for learning how to write unique automation testing programs. It is a must-have book for those Java developers that prioritize code quality as well as have a knack for writing unit, integration, and automation tests.","amazon_rating": 4.1,"release_date": "2007-10-22","tags": ["Software Architecture", "Software Design & Engineering", "Java Programming"]}
{"index":{"_index":"books","_id":"8"}}
{"title": "Head First Object-Oriented Analysis Design","author": "Brett D. McLaughlin, Gary Pollice & David West","edition": 1,"synopsis": "Head First is one of the most beautiful finest book series ever written on Java programming language. Another gem in the series is the Head First Object-Oriented Analysis Design.","amazon_rating": 3.9,"release_date": "2014-04-29","tags": ["Introductory & Beginning Programming", "Object-Oriented Software Design", "Java Programming"]}
{"index":{"_index":"books","_id":"9"}}
{"title": "Java Performance: The Definite Guide","author": "Scott Oaks","edition": 1,"synopsis": "Garbage collection, JVM, and performance tuning are some of the most favorable aspects of the Java programming language. It educates readers about maximizing Java threading and synchronization performance features, improve Java-driven database application performance, tackle performance issues","amazon_rating": 4.1,"release_date": "2014-03-04","tags": ["Design Pattern Programming", "Object-Oriented Software Design", "Computer Programming Language & Tool"]}
{"index":{"_index":"books","_id":"10"}}
{"title": "Head First Design Patterns", "author": "Eric Freeman & Elisabeth Robson with Kathy Sierra & Bert Bates","edition": 10,"synopsis": "Head First Design Patterns is one of the leading books to build that particular understanding of the Java programming language." ,"amazon_rating": 4.5,"release_date": "2014-03-04","tags": ["Design Pattern Programming", "Object-Oriented Software Design eTextbooks", "Web Development & Design eTextbooks"]}
{"index":{"_index":"books","_id":"11"}}
{"title": "JavaScript - The Definitive Guide", "author": "David Flanagan","edition": 1,"synopsis": "JavaScript is the programming language of the web and is used by more software developers today than any other programming language. For nearly 25 years this best seller has been the go-to guide for JavaScript programmers." ,"amazon_rating": 4.7,"release_date": "2020-05-29","tags": ["Design Pattern Programming", "Object-Oriented Software Design eTextbooks", "Programming Languages, Javascript Programming"]}
{"index":{"_index":"books","_id":"12"}}
{"title": "Eloquent Javascript", "author": "Marijn Haverbeke","edition": 3,"synopsis": "JavaScript lies at the heart of almost every modern web application, from social apps like Twitter to browser-based game frameworks like Phaser and Babylon. Though simple for beginners to pick up and play with, JavaScript is a flexible, complex language that you can use to build full-scale applications." ,"amazon_rating": 4.6,"release_date": "2018-12-14","tags": ["DOM", "Node.js","object-oriented and functional programming techniques", "Programming Languages, Javascript Programming"]}
{"index":{"_index":"books","_id":"13"}}
{"title": "JavaScript and JQuery: Interactive Front–End Web", "author": "Jon Duckett","edition": 1,"synopsis": "This full-color book adopts a visual approach to teaching JavaScript & jQuery, showing you how to make web pages more interactive and interfaces more intuitive through the use of inspiring code examples, infographics, and photography." ,"amazon_rating": 4.7,"release_date": "2014-07-18","tags": ["DJavaScript and jQuery", "JavaScript APIs, and jQuery plugins", "Programming Languages, Javascript Programming"]}
{"index":{"_index":"books","_id":"14"}}
{"title": "A Smarter Way to Learn JavaScript", "author": "Mark Myers","edition": 1,"synopsis": "JThe first problem is retention. You remember only ten or twenty percent of what you read. That spells failure. To become fluent in a computer language, you have to retain pretty much everything." ,"amazon_rating": 4.6,"release_date": "2014-03-20","tags": ["Programming Languages, Javascript Programming"]}
{"index":{"_index":"books","_id":"15"}}
{"title": "Head First JavaScript Programming", "author": "Eric T. Freeman and Elisabeth Robson","edition": 1,"synopsis": "This brain-friendly guide teaches you everything from JavaScript language fundamentals to advanced topics, including objects, functions, and the browser’s document object model." ,"amazon_rating": 4.5,"release_date": "2014-04-10","tags": ["The secrets of JavaScript types", "The inner details of JavaScript", "Programming Languages, Javascript Programming"]}
{"index":{"_index":"books","_id":"16"}}
{"title": "Modern JavaScript for the Impatient", "author": "Cay Horstmann","edition": 1,"synopsis": "Modern JavaScript for the Impatient is a complete yet concise guide to JavaScript E6 and beyond. Rather than first requiring you to learn and transition from older versions, it helps you quickly get productive with today’s far more powerful versions and rapidly move from languages such as Java, C#, C, or C++." ,"amazon_rating": 4.9,"release_date": "2020-08-18","tags": ["modern JavaScript", "Object-Oriented Programming", "JavaScript libraries, frameworks, and platforms"]}
{"index":{"_index":"books","_id":"17"}}
{"title": "JavaScript in easy steps", "author": "Mike McGrath","edition": 6,"synopsis": "JavaScript in easy steps, 6th edition instructs the user how to create exciting web pages that employ the power of JavaScript to provide functionality. You need have no previous knowledge of any scripting language so it's ideal for the newcomer to JavaScript. By the end of this book you will have gained a sound understanding of JavaScript and be able to add exciting dynamic scripts to your own web pages." ,"amazon_rating": 4.4,"release_date": "2020-02-28","tags": ["Get Started in JavaScript", "Interact with the Document", "Create Web Applications"]}
{"index":{"_index":"books","_id":"18"}}
{"title": "JavaScript: The Good Parts", "author": "Douglas Crockford","edition": 1,"synopsis": "Most programming languages contain good and bad parts, but JavaScript has more than its share of the bad, having been developed and released in a hurry before it could be refined. This authoritative book scrapes away these bad features to reveal a subset of JavaScript that's more reliable, readable, and maintainable than the language as a whole—a subset you can use to create truly extensible and efficient code." ,"amazon_rating": 4.5,"release_date": "2008-05-18","tags": ["Design Pattern Programming", "Object-Oriented Programming", "Programming Languages, Javascript Programming"]}
{"index":{"_index":"books","_id":"19"}}
{"title": "JavaScript Everywhere", "author": "Adam Scott","edition": 1,"synopsis": "JavaScript is the little scripting language that could. Once used chiefly to add interactivity to web browser windows, JavaScript is now a primary building block of powerful and robust applications. In this practical book, new and experienced JavaScript developers will learn how to use this language to create APIs as well as web, mobile, and desktop applications." ,"amazon_rating": 4.5,"release_date": "2020-02-21","tags": ["Building Cross-platform Applications with GraphQL, React, React Native, and Electron", "Programming Languages, Javascript Programming"]}
{"index":{"_index":"books","_id":"20"}}
{"title": "JavaScript The Complete Reference", "author": "Thomas A. Powell and Fritz Schneider","edition": 3,"synopsis": "Design, debug, and publish high-performance web pages and applications using tested techniques and best practices from expert developers. The all-new edition of this comprehensive guide has been thoroughly revised and expanded to cover the latest JavaScript features, tools, and programming methods." ,"amazon_rating": 4.3,"release_date": "2012-09-16","tags": ["XMLHttpRequest object to create Ajax applications", "DOM", "Programming Languages, Javascript Programming"]}
{"index":{"_index":"books","_id":"21"}}
{"title": "The C# Player's Guide", "author": "RB Whitaker","edition": 5,"synopsis": "The book in your hands is a different kind of programming book. Like an entertaining video game, programming is an often challenging but always rewarding experience. This book shakes off the dusty, dull, dryness of the typical programming book, replacing it with something more exciting and flavorful: a bit of humor, a casual tone, and examples involving dragons and asteroids instead of bank accounts and employees." ,"amazon_rating": 5.0,"release_date": "2022-01-14","tags": ["basic mechanics of C#", "object-oriented programming", "advanced C# features"]}
{"index":{"_index":"books","_id":"22"}}
{"title": "C# 10 and .NET 6", "author": "Mark J. Price","edition": 1,"synopsis": "You will learn object-oriented programming, writing, testing, and debugging functions, implementing interfaces, and inheriting classes. The book covers the .NET APIs for performing tasks like managing and querying data, monitoring and improving performance, and working with the filesystem, async streams, serialization, and encryption. It provides examples of cross-platform apps you can build and deploy, such as websites and services using ASP.NET Core." ,"amazon_rating": 4.6,"release_date": "2021-11-09","tags": ["real-world applications", "latest features of C# 10 and .NET 6", "Visual Studio 2022 and Visual Studio Code"]}
{"index":{"_index":"books","_id":"23"}}
{"title": "C# Programming in easy steps", "author": "Mike McGrath","edition": 2,"synopsis": "C# Programming in easy steps, 2nd edition will teach you to code applications, and demonstrates every aspect of the C# language you will need to produce professional programming results. Its examples provide clear syntax-highlighted code showing C# language basics including variables, arrays, logic, looping, methods, and classes." ,"amazon_rating": 4.6,"release_date": "2020-05-29","tags": ["programming in C#", "creating apps", "fundamental understanding of C#"]}
{"index":{"_index":"books","_id":"24"}}
{"title": "Professional C# and .NET", "author": "Christian Nagel","edition": 1,"synopsis": "Experienced programmers making the transition to C# will benefit from the author’s in-depth explorations to create Web- and Windows applications using ASP.NET Core, Blazor, and WinUI using modern application patterns and new features offered by .NET including Microservices deployed to Docker images, GRPC, localization, asynchronous streaming, and much more." ,"amazon_rating": 4.5,"release_date": "2022-03-04","tags": ["extension of .NET to non-Microsoft platforms like OSX and Linux", "Microsoft Azure services such as Azure App", "C# 10 and .NET 6"]}
{"index":{"_index":"books","_id":"25"}}
{"title": "Head First C#", "author": "Stellman, Andrew, Greene and Jennifer","edition": 4,"synopsis": "What will you learn from this book? For beginning programmers looking to learn C#, this practical guide provides a bright alternative to the legions of dull tutorials on this popular object-oriented language." ,"amazon_rating": 4.6,"release_date": "2021-01-29","tags": ["Real-World Programming with C# and .Net Core", "Object-oriented language", "multi-sensory learning"]}
{"index":{"_index":"books","_id":"26"}}
{"title": "C# 9.0 in a Nutshell", "author": "Albahari and Joseph","edition": 1,"synopsis": "When you have questions about C# 9.0 or .NET 5, this bestselling guide has the answers. C# is a language of unusual flexibility and breadth, but with its continual growth, there's so much more to learn. In the tradition of O'Reilly's Nutshell guides, this thoroughly updated edition is simply the best one-volume reference to the C# language available today." ,"amazon_rating": 4.5,"release_date": "2021-03-31","tags": ["C# and .NET", "pointers, closures, and patterns Dig deep into LINQ", "Programming Languages"]}
{"index":{"_index":"books","_id":"27"}}
{"title": "C# in Depth", "author": "Jon Skeet","edition": 4,"synopsis": "C# is an amazing language that's up to any challenge you can throw at it. As a C# developer, you also need to be up to the task." ,"amazon_rating": 4.6,"release_date": "2019-05-20","tags": ["C# 5, 6, and 7", "better code with tuples, string interpolation, pattern matching"]}
{"index":{"_index":"books","_id":"28"}}
{"title": "C# Data Structures and Algorithms", "author": "Marcin Jamro","edition": 1,"synopsis": "Data structures allow organizing data efficiently. They are critical to various problems and their suitable implementation can provide a complete solution that acts like reusable code. In this book, you will learn how to use various data structures while developing in the C# language as well as how to implement some of the most common algorithms used with such data structures." ,"amazon_rating": 4.6,"release_date": "2018-04-19","tags": ["Implement algorithms", "Build enhanced applications by using hashtables, dictionaries and sets", "Programming Languages, C#"]}
{"index":{"_index":"books","_id":"29"}}
{"title": "Learning C# by Developing Games with Unity 3D", "author": "Terry Norton","edition": 1,"synopsis": "For the absolute beginner to any concept of programming, writing a script can appear to be an impossible hurdle to overcome. The truth is, there are only three simple concepts to understand: 1) having some type of information; 2) using the information; and 3) communicating the information. Each of these concepts is very simple and extremely important. These three concepts are combined to access the feature set provided by Unity." ,"amazon_rating": 3.9,"release_date": "2013-09-25","tags": ["Unity C# scripts", "GameObjects and Component objects", "Unity's Scripting"]}
{"index":{"_index":"books","_id":"30"}}
{"title": "Pro C# 9 with .NET 5", "author": "Andrew Troelsen and Phillip Japikse","edition": 1,"synopsis": "This essential classic provides a comprehensive foundation in the C# programming language and the framework it lives in. Now in its 10th edition, you will find the latest C# 9 and .NET 5 features served up with plenty of \"behind the curtain\" discussion designed to expand developers’ critical thinking skills when it comes to their craft. Coverage of ASP.NET Core, Entity Framework Core, and more, sits alongside the latest updates to the new unified .NET platform, from performance improvements to Windows Desktop apps on .NET 5, updates in XAML tooling, and expanded coverage of data files and data handling. Going beyond the latest features in C# 9, all code samples are rewritten for this latest release." ,"amazon_rating": 4.7,"release_date": "2021-06-08","tags": ["C# 9 features", "ASP.NET Core web applications and web services", "C# and modern frameworks for services"]}
{"index":{"_index":"books","_id":"31"}}
{"title": "Python Crash Course", "author": "Eric Matthes","edition": 2,"synopsis": "Reading books is a kind of enjoyment. Reading books is a good habit. We bring you a different kinds of books. You can carry this book where ever you want. It is easy to carry. It can be an ideal gift to yourself and to your loved ones. Care instruction keep away from fire." ,"amazon_rating": 4.7,"release_date": "2019-05-09","tags": ["Software Architecture", "Functional Programming", "General Introduction to Programming"]}
{"index":{"_index":"books","_id":"32"}}
{"title": "Automate The Boring Stuff With Python", "author": "Al Sweigart","edition": 2,"synopsis": "Reading books is a kind of enjoyment. Reading books is a good habit. We bring you a different kinds of books. You can carry this book where ever you want. It is easy to carry. It can be an ideal gift to yourself and to your loved ones. Care instruction keep away from fire." ,"amazon_rating": 4.7,"release_date": "2019-10-17","tags": ["Software Architecture", "Functional Programming", "General Introduction to Programming"]}
{"index":{"_index":"books","_id":"33"}}
{"title": "Python Projects for Beginners", "author": "Connor P. Milliken","edition": 1,"synopsis": "Immerse yourself in learning Python and introductory data analytics with this book’s project-based approach. Through the structure of a ten-week coding bootcamp course, you’ll learn key concepts and gain hands-on experience through weekly projects." ,"amazon_rating": 4.7,"release_date": "2019-11-16","tags": ["Python language", "Python Data Analysis library", "Anaconda, Jupyter Notebooks, and the Python Shell"]}
{"index":{"_index":"books","_id":"34"}}
{"title": "Python All-in-One For Dummies", "author": "John C. Shovic and Alan Simpson","edition": 2,"synopsis": "Powerful and flexible, Python is one of the most popular programming languages in the world. It's got all the right stuff for the software driving the cutting-edge of the development world—machine learning, robotics, artificial intelligence, data science, etc. The good news is that it’s also pretty straightforward to learn, with a simplified syntax, natural-language flow, and an amazingly supportive user community." ,"amazon_rating": 4.3,"release_date": "2021-04-09","tags": ["Python Building Blocks", "Artificial Intelligence and Python", "Data Science and Python"]}
{"index":{"_index":"books","_id":"35"}}
{"title": "Learning Python", "author": "Mark Lutz ","edition": 1,"synopsis": "Get a comprehensive, in-depth introduction to the core Python language with this hands-on book. Based on author Mark Lutz’s popular training course, this updated fifth edition will help you quickly write efficient, high-quality code with Python. It’s an ideal way to begin, whether you’re new to programming or a professional developer versed in other languages." ,"amazon_rating": 4.5,"release_date": "2013-07-06","tags": ["Software quality", "Enjoyment", "Powerful Object-Oriented Programming"]}
{"index":{"_index":"books","_id":"36"}}
{"title": "Data Structure and Algorithmic Thinking with Python", "author": "Narasimha Karumanchi","edition": 1,"synopsis": "\"Data Structure and Algorithmic Thinking with Python\" is designed to give a jump-start to programmers, job hunters and those who are appearing for exams. All the code in this book are written in Python. It contains many programming puzzles that not only encourage analytical thinking, but also prepares readers for interviews. This book, with its focused and practical approach, can help readers quickly pick up the concepts and techniques for developing efficient and effective solutions to problems." ,"amazon_rating": 4.2,"release_date": "2015-01-29","tags": ["Algorithmic Programming", "Introduction to Programming", "Python Programming"]}
{"index":{"_index":"books","_id":"37"}}
{"title": "Python for Data Analysis", "author": "Wes Mckinney","edition": 2,"synopsis": "Get complete instructions for manipulating, processing, cleaning, and crunching datasets in Python. Updated for Python 3.6, the second edition of this hands-on guide is packed with practical case studies that show you how to solve a broad set of data analysis problems effectively. You’ll learn the latest versions of pandas, NumPy, IPython, and Jupyter in the process. " ,"amazon_rating": 4.6,"release_date": "2017-11-03","tags": ["pandas, NumPy, IPython, and Jupyter", "Python Programming", "Data Analytics"]}
{"index":{"_index":"books","_id":"38"}}
{"title": "Effective Pandas", "author": "Matt Harrison", "edition": 1, "synopsis": "Best practices for manipulating data with Pandas. This book will arm you with years of knowledge and experience that are condensed into an easy to follow format. Rather than taking months reading blogs and websites and searching mailing lists and groups, this book will teach you how to write good Pandas code." ,"amazon_rating": 4.9,"release_date": "2021-12-08","tags": ["Data Manipulation", "Visualization", "Programming Languages"]}
{"index":{"_index":"books","_id":"39"}}
{"title": "Python by Example", "author": "Terry Norton","edition": 1,"synopsis": "Python is today's fastest growing programming language. This engaging and refreshingly different guide breaks down the skills into clear step-by-step chunks and explains the theory using brief easy-to-understand language. Rather than bamboozling readers with pages of mind-numbing technical jargon, this book includes 150 practical challenges, putting the power in the reader's hands." ,"amazon_rating": 4.5,"release_date": "2019-06-06","tags": ["Introduction To Programming", "Python Programming"]}
{"index":{"_index":"books","_id":"40"}}
{"title": "Python Distilled", "author": "David Beazley","edition": 1,"synopsis": "The richness of modern Python challenges developers at all levels. How can programmers who are new to Python know where to begin without being overwhelmed? How can experienced Python developers know they're coding in a manner that is clear and effective? How does one make the jump from learning about individual features to thinking in Python at a deeper level? Dave Beazley's new Python Distilled addresses these and many other real-world issues." ,"amazon_rating": 4.7,"release_date": "2021-11-09","tags": ["Introduction To Programming", "Python Programming"]}
{"index":{"_index":"books","_id":"41"}}
{"title": "Kotlin Programming", "author": "Josh Skeen, Andrew Bailey and David Greenhalgh","edition": 1,"synopsis": "Kotlin is a statically typed programming language designed to interoperate with Java and fully supported by Google on the Android operating system. It is also a multiplatform language that can be used to write code that can be shared across platforms including macOS, iOS, Windows, and JavaScript." ,"amazon_rating": 5.0,"release_date": "2022-01-13","tags": ["Kotlin Essentials", "Kotlin concepts and foundational APIs"]}
v {"index":{"_index":"books","_id":"42"}}
{"title": "Java to Kotlin", "author": "Duncan McGregor and Nat Pryce","edition": 1,"synopsis": "It takes a week to travel the 8,000 miles overland from Java to Kotlin. If you're an experienced Java developer who has tried the Kotlin language, you were probably productive in about the same time. " ,"amazon_rating": 5.0,"release_date": "2021-08-24","tags": ["Kotlin from scratch", "mixed language codebase"]}
{"index":{"_index":"books","_id":"43"}}
{"title": "Kotlin in Action", "author": "DDmitry Jemerov","edition": 1,"synopsis": "Kotlin is a new programming language targeting the Java platform. It offers on expressiveness and safety without compromising simplicity,seamless interoperability with existing Java code, and great tooling support. Because Kotlin generates regular Java bytecode and works together with existing Java libraries and frameworks, it can be used almost everywhere where Java is used today - for server-side development, Android apps, and much more." ,"amazon_rating": 4.7,"release_date": "2017-03-27","tags": ["IMobile Phone Programming", "Introduction to Programming
"]}
{"index":{"_index":"books","_id":"44"}}
{"title": "Head First Kotlin", "author": "Dawn Griffiths and David Griffiths","edition": 1,"synopsis": "This hands-on book helps you learn the Kotlin language with a unique method that goes beyond syntax and how-to manuals, and teaches you how to think like a great Kotlin developer. You ll learn everything from language fundamentals to collections, generics, lambdas, and higher-order functions." ,"amazon_rating": 4.4,"release_date": "2019-02-28","tags": ["Introduction To Programming", "Kotlin language"]}
{"index":{"_index":"books","_id":"45"}}
{"title": "Kotlin Cookbook", "author": "Ken Kousen","edition": 1,"synopsis": "Use Kotlin to build Android apps, web applications, and more—while you learn the nuances of this popular language. With this unique cookbook, developers will learn how to apply thisJava-based language to their own projects. Both experienced programmers and those new to Kotlin will benefit from the practical recipes in this book." ,"amazon_rating": 4.4,"release_date": "2019-11-22","tags": ["Introduction To Programming", "Mobile Phone Programming", "Android and Spring"]}
{"index":{"_index":"books","_id":"46"}}
{"title": "The Joy of Kotlin", "author": "Pierre-Yves Saumont Saumont","edition": 1,"synopsis": "The Joy of Kotlin teaches readers the right way to code in Kotlin. This insight-rich book covers everything needed to master the Kotlin language while exploring coding techniques that will make readers better developers no matter what language they use." ,"amazon_rating": 4.3,"release_date": "2019-05-20","tags": ["Introduction To Programming", "Safe handling of errors and exceptions", "Dealing with optional data"]}
{"index":{"_index":"books","_id":"47"}}
{"title": "Discovering Statistics Using R", "author": "Andy Field, Jeremy Miles and Zoe Field","edition": 1,"synopsis": "Discovering Statistics Using R takes students on a journey of statistical discovery using R, a free, flexible and dynamically changing software tool for data analysis that is becoming increasingly popular across the social and behavioural sciences throughout the world." ,"amazon_rating": 4.5,"release_date": "2012-03-22","tags": ["Programming Languages & Tools", "Psychological Methodology", "R Programming"]}
{"index":{"_index":"books","_id":"48"}}
{"title": "R for Data Science", "author": "Garrett Grolemund and Hadley Wickham","edition": 1,"synopsis": "What exactly is data science? With this book, you’ll gain a clear understanding of this discipline for discovering natural laws in the structure of data. Along the way, you’ll learn how to use the versatile R programming language for data analysis." ,"amazon_rating": 4.7,"release_date": "2016-07-25","tags": ["Data Wrangling", "Data Visualization", "Exploratory Data Analysis"]}
{"index":{"_index":"books","_id":"49"}}
{"title": "Geocomputation with R", "author": "Robin Lovelace, Jakub Nowosad and Jannes Muenchow","edition": 1,"synopsis": "Geocomputation with R is for people who want to analyze, visualize and model geographic data with open source software. It is based on R, a statistical programming language that has powerful data processing, visualization, and geospatial capabilities." ,"amazon_rating": 5.0,"release_date": "2019-03-21","tags": ["Geocomputation", "R Programming"]}
{"index":{"_index":"books","_id":"50"}}
{"title": "R Cookbook", "author": "Jd Long and Paul Teetor","edition": 1,"synopsis": "Perform data analysis with R quickly and efficiently with more than 275 practical recipes in this expanded second edition. The R language provides everything you need to do statistical work, but its structure can be difficult to master. These task-oriented recipes make you productive with R immediately. Solutions range from basic tasks to input and output, general statistics, graphics, and linear regression." ,"amazon_rating": 4.6,"release_date": "2019-07-12","tags": ["Data Analysis, Statistics, and Graphics", "R Programming"]}现在我们知道了 match query 的格式，让我们看一个示例，我们要在 titlefield 中搜索带有 Java 的 Java 书籍。 下面的清单演示了这一点，将 title field 设置为单词 Java 作为要搜索的文本。
GET books/_search
{
"query": {
"match": {
"title": "Java"
}
}
}如清单所示，我们正在创建一个匹配查询，其搜索条件是在标题字段中搜索单词。 Elasticsearch 按预期获取所有与 title 字段中的单词 Java 匹配的文档。
Match 查询分析
不分析术语（term）级查询。 另一方面，对适用于文本字段的匹配查询进行了分析。 在索引过程中使用的相同分析器（除非搜索查询是用不同的分析器明确定义的）处理匹配查询中的搜索词。 如果在我们的文档索引期间使用标准分析器（默认分析器），则在执行搜索之前使用相同的标准分析器分析搜索词。
此外，标准分析器将相同的小写分词过滤器（请记住，在索引期间应用小写标记过滤器）到搜索词。 因此，如果你提供大写的搜索关键字，它们将被转换为小写字母并根据倒排索引进行搜索。 例如，如果我们将 title 值更改为使用大写条件，例如 "title": "JAVA"，然后重新运行查询，结果与上面 的搜索查询相同。如果将 title 值更改为 小写或任何其他方式（例如 java、java 等），查询仍会返回相同的结果。有关分词的部分，请参考文章 “Elasticsearch: analyzer”。
搜索多个词
在我们之前的代码示例（之前的清单）中，我们使用单个词 (Java) 作为针对 title 字段的搜索条件。 我们可以扩展此标准以适应在单个字段中搜索多个单词或一个句子。 例如，我们可以在标题字段中搜索 Java Complete Guide 或在概要字段中搜索 Concurrency and Multithreading，等等。 事实上，搜索一串单词（如断句）比搜索单个单词更常见。 以下清单中的查询正是这样做的。
GET books/_search
{
"query": {
"match": {
"title": {
"query": "Java Complete Guide"
}
}
},
"highlight": {
"fields": {
"title": {}
}
}
}在这里，我们的目的是搜索特定 title（Java Complete Guide）。 也就是说，我们想获取一本名为 “Jav Complete Guid” 的书，如果有的话，如果没有，则什么也不会返回。 但是，如果我们用这些单词执行查询，你可能会惊讶地看到更多文档，而不仅仅是与搜索查询完全匹配的文档。
这种行为的原因是默认情况下，Elasticsearch 默认使用 OR 布尔运算符，因此它可以获取与任何单词匹配的所有文档。 这些单词是单独匹配的，而不是作为短语：在我们的示例中，Elasticsearch 搜索 Java 并返回相关文档，然后对完成的另一个搜索将结果添加到列表中，依此类推。 查询返回 Java，Complete 或 Guide，包括单词的组合作为结果。
默认情况下，Elasticsearch 在搜索一组世界时使用 OR 操作符（正如你可能已经猜到的那样）。 与下一个列表所示，可以重写上面给出的列表中的同一搜索（尽管 OR 操作符是冗余）。
GET books/_search
{
"query": {
"match": {
"title": {
"query": "Java Complete Guide",
"operator": "OR"
}
}
}
}如果要更改此行为以查找 title 中包含所有三个词的文档，则需要启用 AND 运算符。 下面的清单显示了这种方法。
GET books/_search
{
"query": {
"match": {
"title": {
"query": "Java Complete Guide",
"operator": "AND"
}
}
}
}此查询尝试查找与所有三个词匹配的一本书或所有书（书名必须包含 Java AND Complete AND Guide）。 但是，在我们的数据集中，我们没有一本名为 Java Complete Guide 的书，因此没有返回任何结果。
至少匹配几个词
OR 和 AND 运算符是相反的条件。 OR 条件获取任一搜索词，AND 条件获取与所有词完全匹配的文档。 如果我们想从给定的词集中找到至少匹配几个词的文档怎么办？ 在前面的例子中，假设我们想要匹配三个词中的至少两个词（例如，Java 和 Guide）。 这就是 minimum_should_matchattribute 派上用场的地方。
minimum_should_match 属性指示应用于匹配文档的最少单词数。 下一个清单演示了这一点。
GET books/_search
{
"query": {
"match": {
"title": {
"query": "Java Complete Guide",
"operator": "OR",
"minimum_should_match": 2
}
}
}
}此查询将匹配至少两个词（minimum_should_matchattribute 设置为 2），并将获取包含给定三个词中两个词的组合的文档。 OR 运算符在这里是多余的，因为它是默认应用的。
注意：在前面的清单中将值设置为 3 与将运算符更改为 AND 一样：所有单词都必须匹配。
使用关键字 fuzziness 修复拼写错误
在搜索东西时，我们有时可能会错误地输入搜索条件（我们都遇到过）； 例如，我们可以发布一个以 Kava 作为搜索条件的查询，而不是搜索 Java 书籍。 我们知道，其目的是搜索 Java 书籍，Elasticsearch 也是如此。 它采用了一个称为模糊性的概念。 简单地说，模糊性是一种纠正用户在查询条件中的拼写错误的机制。
模糊性对字符串输入进行字符更改，使其与索引中可能存在的字符串相同。 它采用 Levenshtein 距离算法来修复不正确的拼写。更多关于 funzziness 的描述请参阅文章 “Elasticsearch：fuzzy 搜索 （模糊搜索）”。
匹配查询还允许我们添加模糊参数来修复拼写错误。 我们可以将其设置为一个数值，其中期望值是 0、1 或 2，分别表示没有、一个或两个字符更改（插入、删除、修改）。 除了设置这些值外，我们还使用 AUTO 设置； 我们通过将 AUTO 设置为其模糊参数来让引擎处理这些变化。 以下清单显示了我们如何使用模糊度（值为 1）来对 Kava 拼写错误进行排序。文章来源：https://www.toymoban.com/news/detail-465344.html
GET books/_search
{
"query": {
"match": {
"title": {
"query": "Kava",
"fuzziness": 1
}
}
}
}同样，我们在文章 “Elasticsearch：使用 fuzziness 来进行搜索” 介绍模糊性和模糊查询，所以如果你对这个实例感到不知所措，请不要担心。 在示例中，当搜索文本字符串 Java Complete Guide 时，我们使用一组词来搜索一本书（或多本书），并且很可能希望将这些词单独处理（如一组搜索词） . 然而，有时我们可能想要搜索一个短语或一个句子。 这就是 match_phrase 查询出现的时候。文章来源地址https://www.toymoban.com/news/detail-465344.html
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