Реферат тақырыбы: The conceptual, logical and physical data models

The primary goal of using data model are:

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  Ensures that all data objects required by the database are accurately represented. Omission of data will lead to creation of faulty reports and produce incorrect results.
  
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  A data model helps design the database at the conceptual, physical and logical levels.
  
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  Data Model structure helps to define the relational tables, primary and foreign keys and stored procedures.
  
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  It provides a clear picture of the base data and can be used by database developers to create a physical database.
  
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  It is also helpful to identify missing and redundant data.
  
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  Though the initial creation of data model is labor and time consuming, in the long run, it makes your IT infrastructure upgrade and maintenance cheaper and faster.
  

1. 
   Conceptual Data Model: This Data Model defines WHAT the system contains. This model is typically created by Business stakeholders and Data Architects. The purpose is to organize, scope and define business concepts and rules.
   
2. 
   Logical Data Model: Defines HOW the system should be implemented regardless of the DBMS. This model is typically created by Data Architects and Business Analysts. The purpose is to developed technical map of rules and data structures.
   
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   Physical Data Model: This Data Model describes HOW the system will be implemented using a specific DBMS system. This model is typically created by DBA and developers. The purpose is actual implementation of the database.