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BCA 2ND SEM DBMS NOTES

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                                      UNIT 1                        BASIC   CONCEPTS OF DBMS Q1   CHARACTERISTICS AND BENEFITS OF A DATABASE? Self-Describing Nature of a Database System A Database System contains not only the database itself but also the descriptions of data structure and constraints (meta-data). This information is used by the DBMS software or database users if needed. This separation makes a database system totally different from the traditional file-based system in which the data definition is a part of application programs. Insulation between Program and Data In the file based system, the structure of the data files is defined in the application programs so if a user wants to change the structure of a file, all the programs that access that file might need to be changed as well. On the other hand, in the database approach, the data structure is stored in the system catalog not in the programs.  Therefore, one change is all that’s needed. Support mu