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U 11 UU UULUIILLIL UI 19) A data dictionary is the DBMS component that: a) stores the definition of data characteristics and relationships b) stores user access profiles c) provides real time access to breakpoints d) None of the above 20) In the context of database security, authorisation is a) Decryption of passwords b) Encryption of passwords c) Checking that a user is who they claim to be d) the granting of a right or privilege that enables a subject legitimate access to a system or system object (such as a table or view) 21) Raid is an acronym for: a) Redundant Array of Integrity Definitions b) Reduced Aspects of Integrity Definitions c) Redundant Array of Independent Disks d) None of the above 22) Examples of data anomalies include: a) Insertion, deletion and modification b) External, internal and conceptual c) Single and double d) None of the above 23) The three main phases of database design are: a) Conceptual, logical and physical b) External, internal and physical c) DDL, DML and SQL d) None of the above 24) Weak entity types in and entity-relationship diagram are said to be: a) Not dependent on any other entity b) Existence dependent on another entity c) Only required for resolution of many-to-many relationships d) None of the above 25) Given two sets Z and Y, Let Z={a,b,c} and Y={2,5} the Cartesian product of Z and Y is: a) ZX Y={(a,b,c),(2,5)} b) Z X Y={(a2,b2,c2),(2,5)} c) ZXY = {(abc25)} d) None of the above