Projection

A Data Document is a multi-dimensional data object, similar to what you would find in a JSON file. When working with a document store, one generally does not interact with entire Documents, but only with a number of fields from those Documents.

Projection refers to the ability to specify which fields or properties of Data Documents should be retrieved or updated.

The combination of fields in a Projection is also called a “sub-model” and it is documented in an Entity Diagram.