Preparing for BIT – IT2301 Database Management Systems, on Rupavahini by Gihan Wikramanayake, 19th July 2001, 2200-2230 hrs.

1. IT2301 Database Management Systems [email_address] PREPARING FOR THE BIT Preparing for BIT 19/07/2001

2. IT2301 Model Question Paper

5. Evolution 1980s Distributed systems 1990s Object-oriented Object-relational Data warehousing (a), (c) (b) Relational, object-relational, data warehousing. (d) SQL, relational , object-oriented.

6. 10) Which of the following is (are) true for database management systems? (a) Provide protection for data against unexpected loss, damage or destruction. (b) Allow maintenance of high quality, consistent and up to date data. (c) Keep data and the programs that manipulate it together. (d) Prevent unauthorised access to data. (e) Do not allow same data element to appear in more than one place. 10) Which of the following is (are) true for database management systems ?

7. Introduction to DBMS (c) Keep data and the programs that manipulate it together. Data Independence (a) Provide protection for data against unexpected loss, damage or destruction. Transaction Management (b) Allow maintenance of high quality, consistent and up to date data. Integrity

8. Introduction to DBMS (a), (b) (d) Prevent unauthorised access to data. Data Security (e) Do not allow same data element to appear in more than one place. Minimise Data Redundancy

9. 11) Which of the following statement(s) is (are) components of DBMS? (a) Data dictionary/directory subsystem (b) Security and integrity subsystem. (c) Database administrator. (d) Users and programmers. (e) Hardware and data. 11) Which of the following statement(s) is (are) components of DBMS ?

11. 12) Which of the following is (are) true for the 3 level architecture? (a) The physical schema should assist to locate the data stored on disk. (b) The logical view of the data provides the view of data for the user. (c) Data authorisation can be specified for the physical schema. (d) Program/data independence is eliminated due to this architecture. (e) New data can be derived with the help of sub-schemas. 12) Which of the following is (are) true for the 3 level architecture ?

12. 3 level architecture (b) The logical view of the data provides the view of data for the user. (c) Data authorisation can be specified for the physical schema. (d) Program/data independence is eliminated due to this architecture. (e) New data can be derived with the help of sub-schemas. (a) The physical schema should assist to locate the data stored on disk.

13. 13) Which of the following can be considered as a part of data dictionary? (a) Metadata (b) The complete set of data records. (c) Data flow diagram of the system (d) System catalog tables. (e) An Entity-Relationship diagram of the schema. 13) Which of the following can be considered as a part of data dictionary ?

14. Data Dictionary (b) The complete set of data records. (c) Data flow diagram of the system (d) System catalog tables. (e) An Entity-Relationship diagram of the schema. (a) Metadata

15. 14) The term used to identify a row of a table in the relational data model is (a) Cardinality (b) Data (c) Data Set (d) Tuple (e) Record 14) The term used to identify a row of a table in the relational data model is (d) Tuple

16. 15) Select the correct statement(s) describing the keys used in a Relational Data Model. (a) A primary key is an attribute that uniquely identifies each row in a relation. (b) A composite key is a primary key that consists of more than one attribute. (c) A foreign key can be an attribute in a relation of a database that draws values from the same domain as a primary key of another relation in the same database. (d) Candidate key is an attribute that uniquely identifies a column in a relation. (e) One field or combination of fields for which more than one record may have the same combination of values is called the secondary key. 15) Select the correct statement(s) describing the keys used in a Relational Data Model .

17. Relational Data Model (b) A composite key is a primary key that consists of more than one attribute. (c) A foreign key can be an attribute in a relation of a database that draws values from the same domain as a primary key of another relation in the same database. (a) A primary key is an attribute that uniquely identifies each row in a relation.

18. Relational Data Model (d) Candidate key is an attribute that uniquely identifies a column in a relation. (e) One field or combination of fields for which more than one record may have the same combination of values is called the secondary key.

19. 16) Which of the following statement(s) is (are) correct with respect of external views? (a) Hide data from unauthorised users. (b) Permit the use of derive attributes. (c) Join attributes from several tables to create a new virtual table for a user. (d) Allows changing the unit of measurement of some stored data. (e) User level security can be implemented 16) Which of the following statement(s) is (are) correct with respect of external views ?

20. External views (b) Permit the use of derive attributes. (c) Join attributes from several tables to create a new virtual table for a user. (d) Allows changing the unit of measurement of some stored data. (e) User level security can be implemented (a) Hide data from unauthorised users.

21. 17) Which of the following are characteristics of a data warehouse? (a) It is an integrated decision support system. (b) It derives data from various operational databases. (c) It uses object-oriented data. (d) Data it uses is volatile. (e) Data it uses is time-variant. 17) Which of the following are characteristics of a data warehouse? 17) Which of the following are characteristics of a data warehouse ?

22. Data Warehouse (b) It derives data from various operational databases. (c) It uses object-oriented data. subject-oriented (d) Data it uses is volatile. Non-volatile (e) Data it uses is time-variant. (a) It is an integrated decision support system.

23. 18) Data partitioning would: (a) Improve efficiency of access to data. (b) Allow local optimisation. (c) Improve security of the data. (d) Reduce complicity of programs (e) Have no impact on data storage space. 18) Data partitioning would:

24. Distributed Databases (b) Allow local optimisation. (c) Improve security of the data. (d) Reduce complicity of programs (e) Have no impact on data storage space. (a) Improve efficiency of access to data.