Database Final Section 6 - Section 7

transaction

A database _____ is a unit of work that is treated as a whole. It is either completed as a unit or failed as a unit.

operation

atomic

In an online bank application that transfers funds from a checking account to a savings account, if a debit is made successfully from the checking account, the _____ property ensures that the corresponding credit is made to the savings account.

isolation

In an online bank application that transfers funds from a checking account to a savings account, the _____ property ensures that another transaction sees the transferred funds in one account or the other, but not in both, nor in neither.

durability

In an online bank application that transfers funds from a checking account to a savings account, the _____ property ensures that the changes made to each account will not be lost due to a computer failure.

Schedule

A ____ is a sequential order of database instructions for multiple transactions.

read uncommitted

In which isolation level can dirty reads occur?

Serializable

Which isolation level prevents dirty, non-repeatable, and phantom reads?

Locking

A database administrator is updating one of the tables in the database. Which of the following techniques can prevent other database administrators from doing concurrent transactions to the same table?

Lock Manager

A _____ is a part of the concurrency system that monitors, grants, and releases locks.

deadlock

In a _____, all transactions come to a halt and remain at a standstill until one of the transactions is aborted.

Timeout

Which deadlock management technique automatically rolls back a transaction when a lock is not released in a fixed period of time?

recovery log

A document that sequentially writes all the database operations is known as a/an _____.

Transaction failure, System failure, and Storage media failure

A recovery system should manage which three failure scenarios?

Transaction failure

The username and password for the database in the configuration file of a web application is incorrect, so the web application cannot connect to the database. Which failure scenario best describes this example?

compensation record

In the recovery log below, line 6 is a/an _____.

1. start T1

2. start T2

3. update T1, AID, Aoriginal, Anew

4. commit T1

5. update T2, BID, Boriginal, Bnew

6. undo T2, BID, Boriginal

7. rollback T2

hot backup

_____ is a recovery technique that creates a nearly synchronized backup of the primary database on another database server.

repeatable read

Refer to the sequence below. What is the isolation level of transaction E?

session begins

SET GLOBAL TRANSACTION ISOLATION LEVEL SERIALIZABLE; session ends

session begins

SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ;

transaction A

transaction B

SET TRANSACTION

ISOLATION LEVEL READ UNCOMMITTED;

transaction C

SET TRANSACTION

ISOLATION LEVEL READ COMMITTED;

transaction D

transaction E

session ends

boundary

A transaction _____ indicates the starting and ending statement of a database transaction.

S2

Refer to the initial Class table, SQL transaction, and final Class table, below. Which SAVEPOINT identifier is used to produce the final Class table?

START TRANSACTION;

SELECT CourseTitle FROM Class; SAVEPOINT S1;

UPDATE Class SET CourseTitle = "Programming in C" WHERE ClassID = 56;

SAVEPOINT S2;

UPDATE Class SET TeacherID = 32412 WHERE ClassID = 56; SAVEPOINT S3;

DELETE FROM Class WHERE ClassID = 80; SAVEPOINT S4;

ROLLBACK TO _____;

UPDATE Class SET TeacherID = 32412 WHERE ClassID = 80;

COMMIT;

SAVEPOINT

_____ allows all executed database instructions to be rolled back and to be restored in a prior transaction state.

CREATE

In MySQL, which of the following SQL operations always commits immediately?

Tools

Which MySQL layer interacts directly with database users and administrators?

API

A developer wishes to link to a database with a utility created in C. Which MySQL component does the developer use for the link?

execution plan

In the query processor layer, the query optimizer generates a/an _____.

buffer manager

Which MySQL component retains data blocks from storage in main memory for possible reuse?

data blocks, file system

A buffer manager retains _____ from the _____ to reduce data access time.

data dictionary

A database admin uses a SHOW statement to retrieve information about objects in a database. This information is contained in a _____.

Web

_____ architecture is an example of a modern multi-tier architecture.

PaaS (Platform as a Service)

An organization uses a database and application development tools through a cloud provider's _____ services.

privacy

Using a cloud-based database comes with risk. _____ is a regulatory risk.

elasticity

A retailer is using a cloud-based transaction database and is experiencing sales fluctuations through the year. The ability for cloud resources to adapt to such change in utilization is called _____.

IaaS (Infrastructure as a Service)

An organization deploys computer processing power and storage through a cloud provider's _____ services.

single

When concurrently processing instructions, a shared memory computer works well with a common data set in a _____ memory space.

Distributed

An organization has a main office and three satellite locations. Data specific to each location is stored locally in which configuration?

no

For integrity purposes, a distributed transaction requires all or _____ nodes to be updated in order to complete the transaction.

Network partition

What occurs when a distributed database experiences a network error and nodes cannot communicate?

Query

Which of the following is NOT a replica type?

two, separate

A replicated database maintains at least _____ or more replicas on _____ storage devices.

group replication

A database admin configures replication for a distributed database. Which technique applies updates to any available node?

replicated

Due to infrequent updates, many distributed databases use a _____ catalog.

with independent local transactions

In a primary/secondary replica update for a distributed database, secondary nodes are updated _____.

in real time, at fixed intervals

Operational data changes _____, while analytic data is updated _____.

redundancy

An operational database contains tables in third normal form. This design reduces _____.

extracted to a temporary database

Data warehouses should be refreshed periodically. To start, all data should be _____.

data warehouse

For reporting purposes, an organization establishes a(n) _____, which is separate from the operational database

integration

During a data _____ phase, a database administrator refreshes a data warehouse and replaces incompatible keys with consistent values.

Dimension

In a data warehouse that uses a dimensional design, a StudentID column is found in which table?

columns, one-many

A hierarchy in a dimension table contains a series of _____ where each has a _____ relationship to the next.

730 (2 years x 365 days)

A date dimension table tracks data for two years. How many rows does the table contain?

fact table, dimension table

A primary key of a _____ is the composite of the foreign keys that reference a _____.

1440 (24 hours x 60 minutes)

A time dimension table tracks throughout a day by minute. How many rows does the table contain?

volatility

What is a concern with using an in-memory database?

embedded database

A database designer suggests using a database that is packaged with a programming language. Which of the following databases is a good choice?

Autonomous

In a federated database, a(n) _____ database operates independently of other databases.

data lake

Raw data that is copied from multiple data sources is called what?

continuously, periodically

In a data lake, data is often loaded _____ rather than _____.