DBMS Multiple choice Questions and Answers-Relational Databases

21.	Row is synonymous with the term:
a.	record
b.	relation
c.	column
d.	field

Answer: (a).record

22.	The primary key is selected from the:
a.	composite keys
b.	determinants
c.	candidate keys
d.	foreign keys

Answer: (c).candidate keys

23.	Which of the following is a group of one or more attributes that uniquely identifies a row?
a.	Key
b.	Determinant
c.	Tuple
d.	Relation

Answer: (a).Key

Answer: (c).two-dimensional table

25.	In the relational model, relationships between relations or tables are created by using:
a.	composite keys
b.	determinants
c.	candidate keys
d.	foreign keys

Answer: (d).foreign keys

26.	Table is synonymous with the term:
a.	record
b.	relation
c.	column
d.	field

Answer: (b).relation

27.	Which of the following is not a restriction for a table to be a relation?
a.	The cells of the table must contain a single value.
b.	All of the entries in any column must be of the same kind.
c.	The columns must be ordered.
d.	No two rows in a table may be identical.

Answer: (c).The columns must be ordered.

28.	A key:
a.	must always be composed of two or more columns.
b.	can only be one column.
c.	identifies a row.
d.	identifies a column.

Answer: (c).identifies a row.

Answer: (a).column of a table.

Answer: (c).row of a table.