Week 1&2

Question 1

What is Big Data?

Answer 1

Larger, more complex data sets, especially from new data sources.

Question 2

What do flat files do?

Answer 2

A flat file, also known as a text database, stores data in a plain text format?

Question 3

What does ASCII stand for?

Answer 3

American Standard Code for Information Interchange.

Question 4

Row synonyms:

Answer 4

Record, tuple.

Question 5

Column synonyms:

Answer 5

Field, attribute, property, element.

Question 6

A table can also be called?

Answer 6

A relation or a file.

Question 7

What is a specific example of an entity called?

Answer 7

Instances.

Question 8

What is a database?

Answer 8

A database is an organized collection of related information stored in a file.

Question 9

What is a DBMS?

Answer 9

A DBMS, or Relational Database Management System, is software designed to store, retrieve, define, and manage data in a database.

Question 10

What is a relational database?

Answer 10

A database that stores data in a structured format, using columns and rows.

Question 11

What is a RDBMS?

Answer 11

A RDBMS, or Relational Database Management System, is a subset DBMS designed specifically for relational databases.

Question 12

What is a primary key?

Answer 12

A unique identifier.

Question 13

What is a foreign key?

Answer 13

An attribute that refers to another entities primary key.

Question 14

What is a composite key?

Answer 14

Composite keys are comprised of at least two columns that, combined, make one primary key.

Question 15

What is an ERD?

Answer 15

An ERD, or Entity-Relationship Diagram, is a type of flowchart that illustrates how entities relate to each other.

Question 16

What is normalization?

Answer 16

The process of organizing data in a database.

Question 17

What is a schema?

Answer 17

A database structure.

Question 18

What is an index?

Answer 18

A data structure used for organizing and retrieving vast amounts of data.

Question 19

What is ACID?

Answer 19

ACID are four properties that can be used to test whether a DBMS can handle transactions.

Atomicity, Consistency, Isolation, and Durability.

Question 20

What is a transaction?

Answer 20

Any change in a DB.

Question 21

What is a dataset?

Answer 21

A collection of data.

Question 22

What is durability?

Answer 22

Durability states that, once committed, the results of a transaction are permanent and survive future system and media failures.

Question 23

What is consistency?

Answer 23

Consistency states that transactions must obey user-defined integrity constraints or be rolled back.

Question 24

What is atomicity?

Answer 24

Atomicity states that the results of a transaction must either be fully committed or rolled back.

Question 25

What is isolation?

Answer 25

Isolation states that the results of a transaction cannot affect other transactions until the transaction is completed.

Question 26

What is data abstraction?

Answer 26

Data abstraction is the process of hiding irrelevant details from users. There are three main levels: External, Conceptual, and Internal.

Question 27

What is the external level?

Answer 27

The external, or view, level of data abstraction is the highest level. It describes the part of the database a specific user is interested in.

Question 28

What is the conceptual level?

Answer 28

The conceptual, or logical, level of data abstraction is the intermediate level. It describes the Database structure of the whole database for the community of users

Question 29

What is the internal level?

Answer 29

The internal, or physical, level of data abstraction is the lowest level. It describes how data is actually stored.

Question 30

What is cardinality?

Answer 30

Cardinality refers to the relationship of data in one table with respect to another table. “One-to-one”, “one-to-many”, and “many-to-many”.

Question 31

What is an attribute?

Answer 31

An attribute is a characteristic common to all or more instances of a particular entity.