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What is Data abstraction? explain in detail ?

 What is Data abstraction? explain in detail ? 

hey everyone today we will talk about what is data abstraction.

Data abstraction

data abstraction refers to the process of hiding irrelevant details from the user.
The need of efficiency has led designed from the complex data structure to represent data in the database.



here the three levels of data abstraction-


1.view level :The highest level of abstraction describe only part of the entire database. Even thought the logical level of user simple structure , complexity remains because of the variety of information stored in a large Database system do not need all this information inserts they need to access only a  part of the Database .The view level of abstraction exists to simplify their interaction with the system . The system may provide many view for the same Database.                                    

2. logical level: The next highest of abstraction what data are stored in the database , and what relationships exits among those data. The logical level thus  describe the entire database in terms of a small number of relatively simple structures . Although implementation of the simple structure , at the logical level may involved complex physical-level structure , the user of the logical level does not need to be aware of this complexity database administrator , who must decide what information to keep in the database , use the logical level of abstraction.


3. physical level : The lowest level of abstraction describe how the data are actually stored . the physical level describe complex how-level data structure in detail.


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