21. A computer checks the ...... of username and password for a match before granting access.

1. 1. Website

   
   
   

   2. network

   
   
   

   3. backup file

   
   
   

   4. database

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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22. An |E-R diagram is a graphic method of presenting

1. 1. primary keys and their relationships

   
   
   

   2. primary keys and their relationships to instances

   
   
   

   3. entity classes and their relationships

   
   
   

   4. entity classes and their relationships to primary keys

   
   
   

   5. None of the above

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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23. In the relational modes, cardinality is termed as

1. 1. number of tuples

   
   
   

   2. number of attributes

   
   
   

   3. number of tables

   
   
   

   4. number of constraints

   
   
   

   5. None of the above

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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24. A logical schema

1. 1. is the entire database

   
   
   

   2. is a standard way of organising information into accessable part

   
   
   

   3. describes how data is actually stored on disk

   
   
   

   4. All of the above

   
   
   

   5. None of the above

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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25. A collection of related files is called a

1. 1. character

   
   
   

   2. field

   
   
   

   3. database

   
   
   

   4. record

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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