Write short note on data models, Database Management System

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Write short note on Data models?

Data models: A data model is an abstract model which elaborates how data is represented and accessed. The term data model has two commonly accepted meanings:

• A data model theory that is a formal description of how data may be structured and accessed.
• A data model instance that is applying a data model theory to create a practical data model instance for a few particular application.

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IT Assignmnet, i need help for assignment ..

i need help for assignment ..

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