Реферат тақырыбы: The conceptual, logical and physical data models

A Conceptual Data Model is an organized view of database concepts and their relationships. The purpose of creating a conceptual data model is to establish entities, their attributes, and relationships. In this data modeling level, there is hardly any detail available on the actual database structure. Business stakeholders and data architects typically create a conceptual data model.

The 3 basic tenants of Conceptual Data Model are

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  Entity: A real-world thing
  
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  Attribute: Characteristics or properties of an entity
  
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  Relationship: Dependency or association between two entities
  

Data model example:

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  Customer and Product are two entities. Customer number and name are attributes of the Customer entity
  
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  Product name and price are attributes of product entity
  
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  Sale is the relationship between the customer and product
  

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  Offers Organisation-wide coverage of the business concepts.
  
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  This type of Data Models are designed and developed for a business audience.
  
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  The conceptual model is developed independently of hardware specifications like data storage capacity, location or software specifications like DBMS vendor and technology. The focus is to represent data as a user will see it in the “real world.”
  

At this Data Modeling level, no primary or secondary key is defined. At this Data modeling level, you need to verify and adjust the connector details that were set earlier for relationships.