Developing with Couchbase Server

Chapter 4. Getting Data In and Out

With Couchbase Server installed, and your chosen client library up and running, it is time to start storing and retrieving information into the database. All of the client libraries use the same basic operations, although they may have different function or methods names. Despite the differences that exist between individual client libraries, the basic operations and how and why you use them are the same.

A basic list of the key Create, Retrieve, Update, and Delete (CRUD) operations is shown in Table 4-1.

Table 4-1. Key CRUD operations

Operation	Description
add(id, document [, expiry])	Add an item if ID doesn’t already exist
set(id, document [, expiry])	Store a document with ID
replace(id, document [, expiry])	Update the document for an existing ID
cas(id, document, check [, expiry])	Update the document for an existing ID providing the check matches
get(id)	Get the specified document
incr(id [, offset])	Increment the document value by offset
decr(id [, offset]	Decrement the document value by offset
append(id, value)	Append the content to the end of the current document
prepend(id, value)	Prepend the content to the beginning of the current document
delete(id)	Delete the specified document

There are, though, common use cases and sequences with the different operations that can be used to achieve different processes and solutions. Let’s look at some of these in the context of a typical web application.

Basic Interface

To start, let’s look at a basic Ruby script that ...