If you are reading this book, then you likely have already installed CouchDB, explored the Futon web administration console, and created a few documents using the cURL command-line tool. You may even have created a CouchApp or other type of application that accesses documents stored in a CouchDB database. However, to use CouchDB for any practical application, you will likely need to create MapReduce views that let you query your database for meaningful data.

If you want to use CouchDB to support real-world applications, you'll need to create MapReduce views that let you query this document-oriented database for meaningful data. With this short and concise ebook, you'll learn how to create a variety of MapReduce views to help you query and aggregate data in CouchDB’s large, distributed datasets.

You'll get step-by-step instructions and lots of sample code to create and explore several MapReduce views through the course of the book, using an example database you construct. To work with these different views, you’ll learn how to use the Futon web administration console and the cURL command line tool that come with CouchDB.

• Learn how the Map and Reduce steps work independently and together to index your data
• Use the example database to create several temporary views based on different criteria
• Discover the uses of Map and Reduce JavaScript functions
• Convert your temporary views to permanent views within a design document
• Learn several options for querying the data within your views
• Limit the number of results returned, skip some results, or reverse the order of the output
• Group your results by exact keys or by parts of keys

  Bradley Holt, co-founder of the creative services firm Found Line, is a web developer and entrepreneur ten years of PHP and MySQL experience. He began using CouchDB before the release of version 1.0. Bradley is an active member of the PHP community, and can be reached at bradley-holt.com.