Editing Object–role modeling (section)

=== Design procedure ===
[[File:Schema for Geologic Surface.svg|thumb|360px|right|Example of the application of Object Role Modeling in a "Schema for Geologic Surface", Stephen M. Richard (1999).<ref name="SMR99">Stephen M. Richard (1999). [http://pubs.usgs.gov/of/1999/of99-386/richard.html Geologic Concept Modeling]. U.S. Geological Survey Open-File Report 99-386.</ref>]]
System development typically involves several stages such as: feasibility study; requirements analysis; conceptual design of data and operations; logical design; external design; prototyping; internal design and implementation; testing and validation; and maintenance.  The seven steps of the conceptual schema design procedure are:<ref name="TH01">Terry Halpin (2001). [http://www.orm.net/pdf/ORMwhitePaper.pdf "Object-Role Modeling: an overview"]</ref>

# Transform familiar information examples into elementary facts, and apply quality checks
# Draw the fact types, and apply a population check
# Check for entity types that should be combined, and note any arithmetic derivations
# Add uniqueness constraints, and check arity of fact types
# Add mandatory role constraints, and check for logical derivations
# Add value, set comparison and subtyping constraints
# Add other constraints and perform final checks

ORM's conceptual schema design procedure (CSDP) focuses on the analysis and design of data.