Test 1

Question 1

What is an attribute?

Answer 1

They are a name and a data type for data

Question 2

database is a tree-like hierarchy, folders with subfolders

Answer 2

Hierarchical

Question 3

database is one big hashmap

Answer 3

Key-Value Pair

Question 4

What is the minimum number of attributes in a relation?

Answer 4

0 called an anti table

Question 5

A relation can be pictured as a…

Answer 5

table

Question 6

a set of attributes whose values with always uniquely identify a tuple in the relation

Answer 6

candidate key

Question 7

constraints to prevent inconsistencies

Answer 7

Data Integrity

Question 8

defines what sort of data is stored

Answer 8

Data Definition Language

Question 9

a super-set of a candidate key

Answer 9

super-key

Question 10

The columns of a table are called …

Answer 10

attributes

Question 11

a set of possible values

Answer 11

domain

Question 12

What are the candidate keys for a tuple with no attributes?

Answer 12

The empty set

Question 13

Every true piece of information is in the database

No false data is in the database

Using null violates the closed universe assumption

Null represents missing information

Answer 13

Closed universe assumption

Question 14

What is the maximum number of attributes in a relation?

Answer 14

No maximum

Question 15

What is a domain

Answer 15

A set of values and a data type

Question 16

accessing and processing data

Answer 16

Data Manipulation Language

Question 17

most common form of database

Answer 17

Relational

Question 18

prevents unauthorized access or modification of data

Answer 18

Data Security

Question 19

Each attributes has an associated

Answer 19

domain

Question 20

DBMS provide..

Answer 20

Data Definition Language,
Data Manipulation Language,
Data Security,
Data Integrity

Question 21

Tables are organized into

Answer 21

schemas

Question 22

a seperation of how data is physically stored and organized from how data is logically accessed

Answer 22

Data Abstraction

Question 23

A relation with 0 attributes, how many tuples can there be in that relation?

Answer 23

1

Question 24

The rows of a table are called

Answer 24

tuples

Question 25

Who invited the relational model?

Answer 25

Edgar Codd

Question 26

used for foreign keys in other relations

Answer 26

primary key

Question 27

database is composed of well-defined relations/tables that reference each other

Answer 27

Relational

Question 28

The operation where we reduce a relation full of data to those rupees in that meet a particular criteria

Answer 28

Selection

Question 29

The operation where a relation is reduced to a specified set of its attributes

Answer 29

Projection

Question 30

Combines two relations by combining their columns, then associations the data in every possible combination

Answer 30

Cross join(Cartesian product)

Question 31

Combining products and selection

Answer 31

Inner join

Question 32

A join that selects for equality on columns that have the same name on both relations and then applies a projection to eliminate duplication

Answer 32

Natural join

Question 33

A relation with all the tuples of both relations

Answer 33

Union

Question 34

A relation containing those tuples which can be found in both relations

Answer 34

Intersection

Question 35

A relation with all the tuples in a except those that are also in b

Answer 35

Difference