Chapter 15

Question 1

database software

Answer 1

is a well thought out collection of computer files

Question 2

ERM entity relationship modeling

Answer 2

a database modeling method used to construct theoretical and conceptual representation of data to produce a schema

Question 3

database schema

Answer 3

is a map of data tables and their relationships to one another

Question 4

relational database

Answer 4

creates a relationship between the different tables, uses. primary key id

Question 5

why use relational databases

Answer 5

keeps infor up to date and reduces redundancy, increases flexibility, its scalable, increases performances, increases integrity of information, reduces error and mistakes that could occur when entering information multiple times, security can lock the tables

Question 6

Cardinality

Answer 6

the number of elements in a set.
high, which means it has a unique value like a bank account or UIN

Question 7

1:M

Answer 7

low, means its repeated more often like a zipcode

Question 8

SQL structured query language

Answer 8

the most widely used standard computer language for relational databases it allows a programmer to manipulate and query data

Question 9

what are the 3 cardinality relationships

Answer 9

1:1 one to one meaning one person has one

M:M many to many (like many customers purchasing many products and can be purchase many products

1:M (1 to many ex: mays has many classrooms one building)

Question 10

what is SQL used for?

Answer 10

extracting data, sorting data, manipulating data

Question 11

whats one field that needs to be unique

Answer 11

primary key

Question 12

what is chen model

Answer 12

rectangle is the table name and ovals are the build names (attributes)