Getting Started with Data Modeling

A data model is a representation of the information consumed and produced by a system. Data modeling involves analyzing the data objects present in a system and the relationships between them. PowerDesigner® provides conceptual, logical, and physical data models to allow you to analyze and model your system at all levels of abstraction.

Suggested Bibliography

Graeme Simsion, Van Nostrand Reinhold, Data Modeling Essentials, 1994, 310 pages; paperbound; ISBN 1850328773
James Martin, Prentice Hall, Information Engineering, 1990, three volumes of 178, 497, and 625 pages respectively; clothbound, ISBN 0-13-464462-X (vol. 1), 0-13-464885-4 (vol. 2), and 0-13-465501-X (vol. 3).
Joe Celko, Joe Celko's SQL for Smarties (Morgan Kaufmann Publishers, Inc., 1995), 467 pages; paperbound; ISBN 1-55860-323-9.

Conceptual Data Models
A conceptual data model (CDM) helps you analyze the conceptual structure of an information system, to identify the principal entities to be represented, their attributes, and the relationships between them. A CDM is more abstract than a logical (LDM) or physical (PDM) data model.
Logical Data Models
A logical data model (LDM) helps you analyze the structure of an information system, independent of any specific physical database implementation. An LDM has migrated entity identifiers and is less abstract than a conceptual data model (CDM), but does not allow you to model views, indexes and other elements that are available in the more concrete physical data model (PDM).
Physical Data Models
A physical data model (PDM) helps you to analyze the tables, views, and other objects in a database, including multidimensional objects necessary for data warehousing. A PDM is more concrete than a conceptual (CDM) or logical (LDM) data model. You can model, reverse-engineer, and generate for all the most popular DBMSs.
Creating a Data Model
You create a new data model by selecting File New Model .