A logical data model is a representation of the business requirements with a particular problem domain. Logical models do not go down to the level of "physical" database features (tables, rows, columns, datatypes, etc.), but can be the basis of physical database design (For example, in logical model, entities often correspond to tables in a physical database design). Logical models focus on the definition of entities, attributes, and key groups (identifiers used to make associations between and among entities).
Data models usually have graphical and textual components and are developed within a particular data management technology or notation. Common notations used for logical models are IDEF1X, UML class, Information Engineering (IE), and Entity Relationship (ER) diagrams.
