DBMS Multiple Choice Questions and Answers

81. Which of the following operations need the participating relations to be unon compatible?

1. UNION
2. INTERSECTION
3. DIFFERENCE
4. All of the above

82. To delete a particular column in a relation the command used is:

1. UPDATE
2. DROP
3. ALTER
4. DELETE

83. A report generator is used to

1. update files.
2. print files on paper.
3. data entry.
4. delete files.

84. The database environment has all of the following components except:

1. users.
2. separate files.
3. database.
4. database administrator.

85. Count function in SQL returns the number of

1. values.
2. distinct values.
3. groups.
4. columns.

86. It is possible to define a schema completely using

1. VDL and DDL.
2. DDL and DML.
3. SDL and DDL.
4. VDL and DML.

87. _________ is a virtual table that draws its data from the result of an SQLSELECT statement.

1. View
2. Synonym
3. Sequence
4. TrAnsaction

88. Which one of the following is not true for a view:

1. View is derived from other tables.
2. View is a virtual table.
3. A view definition is permanently stored as part of the database.
4. View never contains derived columns.