Apache CouchDB

Apache CouchDB is a distributed, fault-tolerant and schema-free document-oriented database accessible via a RESTful HTTP/JSON API. Among other features, it provides robust, incremental replication with bi-directional conflict detection and resolution, and is queryable and indexable using a table-oriented view engine with JavaScript acting as the default view definition language.

Apache CouchDB Sketch

CouchDB is written in Erlang, but can be easily accessed from any environment that provides means to make HTTP requests. There are a multitude of third-party client libraries that make this even easier for a variety of programming languages and environments.

Install

Windows

先安装 Erlang, 再安装 CouchDB

启动 C:\erl5.7.2\bin\couch_start.bat

访问 http://localhost:5984/_utils/index.html

更多细节: http://wiki.apache.org/couchdb/Installing_on_Windows

Database

A CouchDB database is a flat collection of these documents.

CouchDB Document

A CouchDB document is simply a JSON object.

A CouchDB document is an object that consists of named fields. Field values may be strings, numbers, dates, or even ordered lists and associative maps. An example of a document would be a blog post:

"Subject": "I like Django"  
"Author": "Allen"  
"PostedDate": "5/23/2009"  
"Tags": ["Python", "Django", "Framework"]
"Body": "Django is a high-level Python Web framework that encourages rapid development and clean, I like Django."

CouchDB Views

Views are the primary tool used for querying and reporting on CouchDB documents. There are two different kinds of views: permanent and temporary views.

Views are defined with Javascript functions. Here is the very simplest function:

function(doc) {
  emit(null, doc);
}

Python

• Couchdbkit
• Using CouchDB with Django
• An Introduction to Using CouchDB with Django

Links

• http://couchdb.apache.org/
• http://wiki.apache.org/couchdb/
• http://groups.google.com/group/couchdb
• http://docs.huihoo.com/apache/couchdb/
• http://download.huihoo.com/apache/couchdb/