This section describes core elements you will use to handle data in Couchbase Server; it will describe the ways you can structure individual JSON documents for your application, how to store the documents from a Couchbase SDK, and describe different approaches you may take when you structure data in documents.

Couchbase Server is a document database; unlike traditional relational databases, you store information in documents rather than table rows. Couchbase has a much more flexible data format; documents generally contains all the information about a data entity, including compound data rather than the data being normalized across tables.

A document is a JSON object consisting of a number of key-value pairs that you define. There is no schema in Couchbase; every JSON document can have its own individual set of keys, although you may probably adopt one or more informal schemas for your data.

As of Couchbase Server 2.0, one of the benefits of using JSON documents is that you can index and query these records. This enables you to collect and retrieve information based on rules you specify about given fields; it also enables you to retrieve records without using the key for the record. For more information about indexing and querying using Couchbase SDK, see Chapter 4, Finding Data with Views.