An attribute is a(n):

	a.	Two-dimensional table.
	b.	column of a table
	c.	row of a table

the set of permitted values for each attribute

	a.	Domain
	b.	Dashed lines
	c.	Rectangles

Output all pairs of rows from the two input relations

	a.	Natural join
	b.	Cartesian product
	c.	Unoin

Output pairs of rows from the two input relations that have the same value on all attributes that have the same name

	a.	Union
	b.	Natural join
	c.	Cartesian product

____ computes the join and then adds tuples form one relation that does not match tuples in the other relation to the result of the join.

	1.	join
	2.	outer join
	3.	cartesian product
	4.	Natural Join

In relation algebra, the symbol U is

	a.	Set different
	b.	Union
	c.	Set intersection

In relation algebra, the symbol - is

	a.	Set intersection
	b.	Set different
	c.	Union

Drawbacks of using file systems to store data

	a.	Data redundancy and inconsistency
	b.	Data isolation
	c.	Difficulty in accessing data
	d.	all above

........ the logical structure of the database

	a.	Schema
	b.	Instance
	c.	Relation
	d.	Diagram

. is a program module that provides the interface between the low-level data stored in the database and the application programs and queries submitted to the system.

	a.	Storage manager
	b.	Transection
	c.	SQL
	d.	Transaction manager