1.3.2 Databases

Question 1

Database

Answer 1

A collection of data or information which is held together in an organised way

Question 2

Flat file database

Answer 2

Consist of a single table which stores all the data within that database

Question 3

Relational Database

Answer 3

A database that has a separate table for each entity.

Question 4

Primary Key

Answer 4

A field in a table which is unique and allows you to identify every record

Question 5

Foreign Key

Answer 5

Used to link tables together and create relationships

Question 6

Compound/composite primary key

Answer 6

Combines more that one field to make a unique value

Question 7

Secondary key

Answer 7

A key made on a field to be indexed for faster searches

Question 8

Referential integrity

Answer 8

Making sure you cannot delete record that are used by other tables

Question 9

Entity relationship modelling/diagram

Answer 9

A diagram that represents the relationships between entities in a database

Question 10

Normalisation

Answer 10

A process used to come up with the best possible design for a relational database

Question 11

Indexing

Answer 11

Creating a database index that improves the speed of data retrieval in a database

Question 12

0NF

Answer 12

A table with no normalisation

Question 13

1NF/ First Normal Form

Answer 13

A table containing no repeated attributes

Question 14

2NF/ Second Normal Form

Answer 14

A table that’s is in first normal form and contains no partial dependencies

Question 15

3NF / Third Normal Form

Answer 15

A table that is in 2NF and all non key elements are fully dependent on the primary key

Question 16

Normal Forms

Answer 16

Ways for structuring data in a relational database according to formal rules

Question 17

SQL / Structured Query Language

Answer 17

A declarative language used for querying and updating tables in a relational database

Question 18

Database transaction

Answer 18

A set of operations that update one or more databases in some way

Question 19

ACID

Answer 19

Atomicity
Consistency
Isolation
Durability

Question 20

Atomic transaction

Answer 20

An atomic transaction is indivisible

Question 21

Consistent transaction

Answer 21

Follows all of the established rules of the database

Question 22

Isolated transaction

Answer 22

Cannot be interfered with while underway

Question 23

Durable transaction

Answer 23

Is recorder is such a way that the result cannot be easily lost

Question 24

Record locking

Answer 24

Preventing simultaneous access to record in a database

Question 25

Redundancy

Answer 25

Having one or more copies of data in physically different locations