A Data Item is a special type of Item that builds upon the flexible structure in which values can be stored. Data items can be thought of as a database row that contains the data for columns belonging to a table. Along these lines, Data Definitions then becomes the table schema themselves. Data definitions and items have deep support within the CMS framework and come with a set of APIs to interact with them directly. A core Data module is also provided to allow for the editing and publishing of each data item. It is important to note that because a Data Item is an enhanced CMS Item, then all other features on an item is also available for a Data Item. This includes security management, user specific drafting, versioning and multi-language support to name a few. By modifying column details on a Data Definitions, all of its Data Item’s value will be automatically validated and updated.
Note: A Data Item is meant for the user defined creation and storing of data structures. Any module can elect to interface with Data Items. For example, the core Form module can render a drop down list to a website user using a selected Data Item for its option items. The Data module only provides a user interface for a CMS User to create and edit the values of a Data Item and by design does not offer a means to render its values to a web site visitor.
Additional Resources
How to: Create a Data Definition
How to: Create a Data Item