Database Systems

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Ø  What are the database system’s main components?


·         Hardware -all of the system’s physical devices
·         Software - operating system software, DBMS software, and application programs and utilities
·         People – System administrator, database administrator, Programmers, End user, database designer
·         Procedures - the instructions and rules that govern the design and use of the database system
·         Data - The word data covers the collection of facts stored in the database.



Ø  The main functions of a database management system (DBMS)

o   Data dictionary management - The DBMS stores definitions of the data elements and their relationships (metadata) in a data dictionary. It provides data abstraction, and it removes structural and data dependency from the system.
o   data storage management
o   data transformation and presentation
o   security management
o   multiuser access control
o   backup and recovery management
o   data integrity management
o   database access languages and application programming interfaces
o   database communication interfaces –
§  End users can generate answers to queries by filling in screen forms through their preferred Web browser.
§  The DBMS can automatically publish predefined reports on a Web site.

§  The DBMS can connect to third-party systems to distribute information via e-mail or other productivity applications.

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