Chapter 1

Question 1

Purpose of a database?

Answer 1

store, manipulate and retrieve data.

Question 2

The data stored in a database should be ______.

Answer 2

durable; data remains consistent and valid

Question 3

A good database system should provide ______, ________, and _______.

Answer 3

CRUD, ACID, and security

Question 4

CRUD

Answer 4

create, read, update and delete

Question 5

Transactions

Answer 5

a single operation or series of operations that retrieves or alters the data in a database.

Question 6

What is the goal of a successful transaction?

Answer 6

to change the database form one consistent state to another consistent state.

Question 7

What are the two results of a transaction?

Answer 7

committed or rolled back

Question 8

A committed transaction

Answer 8

the results of the transaction are written to the database, resulting in a new consistent state (a commit).

Question 9

A Rollback

Answer 9

the database is placed back into the consistent state it was in before the transaction started.

Question 10

ACID

Answer 10

Atomicity, OCnsistencyy, Isolation, Durability

Question 11

Atomicity

Answer 11

The transaction is a complete unit, and is executed in its entirety or not at all

Question 12

Consistency

Answer 12

a transaction changes the database from one consistent state to another consistent state or the transaction is rolled back

Question 13

Isolation

Answer 13

An incomplete transaction should not be visible to others. Users only see the previous consistent state or the resulting consistent state (not the inconsistent state as the transaction is completed)

Question 14

Durability

Answer 14

Committed transactions are permanent. (Once committed, it cannot be rolled back.)

Question 15

Database security is accomplished through. . .

Answer 15

a combination of physical, network access and design methods.