
Overview of Relational DBMS
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a DBMS. In a top-down manner, the different levels of these functionalities can be expressed as
application interface, security control, compilation, execution, data access and consistency con-
trol. The application interface level manages interfaces to the user’s applications. The security
control level is responsible for maintaining data integrity and authorization checking. The query
processing module of an RDBMS is responsible for processing queries and retrieving data from the
database. This task is performed collectively by three different levels, namely, compilation, execution
and data access. The consistency ...