A conceptual schema is a high-level description of informational needs underlying the design of a database.[citation needed] It typically includes only the main concepts and the main relationships among them. Typically this is a first-cut model, with insufficient detail to build an actual database. This level describes the structure of the whole database for a group of users. The conceptual model is also known as the data model that can be used to describe the conceptual schema when a database system is implemented.[citation needed] It hides the internal details of physical storage and targets on describing entities, datatypes, relationships and constraints.

Data Structure Diagram.

A data structure diagram (DSD) is a data model or diagram used to describe conceptual data models by providing graphical notations which document entities and their relationships, and the constraints that bind them.

See also