The views module allows administrators and site designers to create, manage, and display lists of content. Each list managed by the views module is known as a "view", and the output of a view is known as a "display". Displays are provided in either block or page form, and a single view may have multiple displays. Optional navigation aids, including a system path and menu item, can be set for each page-based display of a view. By default, views may be created that list content (a Node view type), content revisions (a Node revisions view type) or users (a User view type). A view may be restricted to members of specific user roles, and may be added, edited or deleted at the views administration page. For more technical users and in terms views can be understood simple as a user interface to compose SQL-queries and to pull information (Content, Users, etc.) from the database and show it on a screen as desired. The "building block" design of the views system provides power and flexibility, allowing parameters to be specified only when needed. While an advanced view may use all of available parameters to create complex and highly interactive applications, a simple content listing may specify only a few options. All views rely on a conceptual framework that includes: Parallels between the components in the Views interface and an sql query:
Sql Query Views Component
SELECT n.title, fields
FROM {node} n base table view type
INNER JOIN {users} u ON n.uid = u.uid relationship
WHERE n.status = 1 filter
AND u.uid = arg(1) argument
ORDER BY n.changed DESC sort