AS7

Question 1

Flat File Database

Answer 1

• Info is held in a single table.
• Column = Attiribute.
• Row = Record.
• Only useful for small amounts of data.
• Larger tables = more chance of data redundancy.
• Easier to create, maintain.

Question 2

Relational Database

Answer 2

• Most commonly used.
• Allows efficient processing.
• Data seperated into tables; each one stores data related to one entity.
• No multiple record changes needed.
• All records have a link to that entry that will show the change.
• Better security/ Confidentiality.

Question 3

An entity

Answer 3

• Represents a real world object.

Question 4

Primary Key

Answer 4

• A field that is a unique identifier for a record.

Question 5

Foreign Key

Answer 5

• A PK from another table that links the tables together.

Question 6

Index

Answer 6

• Data structure that shortens the length of time it takes to search a database.

Question 7

Entity Relationship Diagram

Answer 7

• Defines the relationship between tables in a relational database.

Question 8

Authorisation Levels in Databases

Answer 8

• Usernames/passwords allow for the system to limit their view of the records.
• Data protection.
• Simplifies access.
• Improves performance.
• Prevents unauthorised edits.
• Users restricted from running queries, deleting records, altering the structure.