Data modeling: Difference between revisions

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In information system design, '''data modeling''' is the analysis and design of the information in the system, concentrating on the logical entities and the logical dependencies among these entities. Data modeling is an [[Abstraction|abstraction]] activity in that the details of the values of individual data observations are ignored in favor of the structure, relationships, names and formats of the data of interest, although a list of valid values is frequently recorded. The resulting [[data model]] shoulddefines not only define the data's structure, but also whatits the data actually means ([[semantics)]].

While ''data analysis'' is a common term for this activity is "data analysis"modeling, the activity actually has more in common with the ideas and methods of [[Synthesis|synthesis]] (putting things together) than it does inwith taking things apart (the original meaning of the term ''[[Analysis|analysis]] (taking things apart''). ThisData is because the activitymodeling strives to bring the data structures of interest together ininto a cohesive, inseparable, whole by eliminating unnecessary data redundancies and by relating data structures bywith [[Relational model|relationships]].

The process of developing the data model involves analyzing the kinds of data that that will generally fit into the information system, and the relationships between different data elements within that system. Then the modeler must come up with representations of data models that guide the software development process. In the early phases of a software development project, emphasis will be on the design of a [[conceptual schema|conceptual data model]]. This can be detailed into a [[logical data model]] sometimes called a [[functional data model]]. In later stages, this model may be translated into [[physical data model]].