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The four views of the model are logical, development, process, and physical view. In addition, selected use cases or scenarios are used to illustrate the architecture serving as the 'plus one' view. Hence, the model contains 4+1 views: [1] Logical view: The logical view is concerned with the functionality that the system provides to end-users.
Data model: A data model defines the objects of a domain, their inter-relationships, and their properties, normally for the purpose of a database design. There are three data model levels, from highest to lowest: conceptual, logical, and physical. Conceptual data models are the highest level. They model the user concepts in terms familiar to users.
Development view: illustrates a system from a programmers perspective and is concerned with software management. Process view: deals with the dynamic aspect of the system, explains the system processes and how they communicate, and focuses on the runtime behavior of the system. Physical view: depicts the system from a system engineer's point of ...
Physical data model options. [1] A physical data model (or database design) is a representation of a data design as implemented, or intended to be implemented, in a database management system. In the lifecycle of a project it typically derives from a logical data model, though it may be reverse-engineered from a given database implementation.
This shows that a data model can be an external model (or view), a conceptual model, or a physical model. This is not the only way to look at data models, but it is a useful way, particularly when comparing models.
A data architecture, in part, describes the data structures used by a business and its computer applications software. Data architectures address data in storage, data in use, and data in motion; descriptions of data stores, data groups, and data items; and mappings of those data artifacts to data qualities, applications, locations, etc.
The physical schema according to Sowa (2004) "describes the internal formats of the data stored in the database, and the external schema defines the view of the data presented to the application programs." [4] The framework attempted to permit multiple data models to be used for external schemata. [5]
The physical structure of the data is referred to as "physical data description". Physical data independence deals with hiding the details of the storage structure from user applications. The application should not be involved with these issues since, conceptually, there is no difference in the operations carried out against the data.