intro - 1 What is database A database is a logically coherent collection of data with some inherent meaning representing some aspect of real world and

intro - 1 What is database A database is a logically...

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1.What is database?A database is a logically coherent collection of data with some inherent meaning,representing some aspect of real world and which is designed, built and populatedwith data for a specific purpose.2.What is DBMS?It is a collection of programs that enables user to create and maintain adatabase. In other words it is general-purpose software that provides the users withthe processes of defining, constructingand manipulatingthe database for variousapplications.3.What is a Database system?4.Advantages of DBMS?5.Disadvantage in File Processing System?6.Describe the three levels of data abstraction?The are three levels of abstraction:Physicallevel: The lowest level of abstraction describes how data are stored.Logical level:The next higher level of abstraction, describes what data are storedin database and what relationship among those data. View level: The highest level of abstraction describes only part of entire database.7.Define the "integrity rules"8.What is extension and intension?
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9.What is System R? What are its two major subsystems?10. How is the data structure of System R different from the relational structure? Unlike Relational systems in System R Domains are not supportedEnforcement of candidate key uniqueness is optionalEnforcement of entity integrity is optionalReferential integrity is not enforced11. What is Data Independence?
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