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Changing short description from "(in software engineering) process of creating a data model for an information system by applying certain formal techniques" to "Creating a model of the data in a system" (Shortdesc helper) |
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The process of designing a database involves producing the previously described three types of schemas - conceptual, logical, and physical. The database design documented in these schemas are converted through a [[Data Definition Language]], which can then be used to generate a database. A fully attributed data model contains detailed attributes (descriptions) for every entity within it. The term "database design" can describe many different parts of the design of an overall [[database system]]. Principally, and most correctly, it can be thought of as the logical design of the base data structures used to store the data. In the [[relational model]] these are the [[table (database)|tables]] and [[view (database)|views]]. In an [[object database]] the entities and relationships map directly to object classes and named relationships. However, the term "database design" could also be used to apply to the overall process of designing, not just the base data structures, but also the forms and queries used as part of the overall database application within the [[Database management system|Database Management System]] or DBMS.
In the process, system [[Interface (computer science)|interface]]s account for 25% to 70% of the development and support costs of current systems. The primary reason for this cost is that these systems do not share a [[common data model]]. If data models are developed on a system by system basis, then not only is the same analysis repeated in overlapping areas, but further analysis must be performed to create the interfaces between them. Most systems within an organization contain the same basic data, redeveloped for a specific purpose. Therefore, an efficiently designed basic data model can minimize rework with minimal modifications for the purposes of different systems within the organization<ref name="MW99"/>
=== Modeling methodologies ===
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