Databases, Compression and Encryption

Question 1

Compression

Answer 1

Reducing the size of a file

Question 1

Asymmetric Encryption

Answer 1

Encryption method that uses a public key to encrypt data and a separate private key to decrypt it

Question 2

Database Normalisation

Answer 2

Formatting relational databases to reduce data redundancy

Question 3

Dictionary Coding

Answer 3

Compression method that uses short keys to represent longer commonly recurring patterns

Question 4

Encryption

Answer 4

Altering data so that it can be understood only by its intended recipient

Question 5

Entity Relationship Modelling

Answer 5

Showing the relationships between different objects

Question 6

Field

Answer 6

Property of an item stored in a database

Question 7

Flat File

Answer 7

Type of database which contains only one table

Question 8

Foreign Key

Answer 8

Field used in one table to represent the value of a primary key in a related table

Question 9

Hashing

Answer 9

Calculating a key from a given value

Question 10

Indexing

Answer 10

Linking values to keys so that they can be quickly accessed by referring to their key

Question 11

Lossless Compression

Answer 11

Method of reducing the size of a file without losing any of the original data

Question 12

Lossy Compression

Answer 12

Method of reducing the size of a file that discards some of the original data

Question 13

Primary Key

Answer 13

Attribute in a table which uniquely identifies each record in that table

Question 14

Relational Database

Answer 14

Database in which two or more tables are linked to each other

Question 15

Run Length Encoding

Answer 15

Data compression method that converts sequences of identical characters into a single value

Question 16

Secondary Key

Answer 16

Non-unique key in a table that is used to quickly search for records in that table

Question 17

SQL

Answer 17

Programming language designed for managing data in relational database management systems

Question 18

Symmetric Encryption

Answer 18

Encryption method that uses the same key to encrypt and decrypt data