ITM 500 Chapter Notes -Oracle Vm Server For Sparc, Unique Key, Data Modeling
Document Summary
Ca erwin data modeler (erwin) is a software tool for data modeling (data requirements analysis, database design etc) of custom developed information systems, including databases of transactional systems and data marts. Logical data modeling: logical only models may be created, from which physical models may be derived. Also combinations logical and physical models are supported. Supports entity-type and attribute logical names and descriptions, logical domains and data types, as well as relationship naming. Physical data modeling: physical only models may be created as well as combination logical and physical models. Supports table and column naming and descriptions, user defined data types, as well as primary key, foreign key, alternate key and check constraint definition and naming. Support for indexes, views, stored procedures and triggers is also included. Choose logical/physical as the new model type. This choice will allow us to switch back and forth easily between a logical model (er diagram) and a physical model (database schema).