Databases

Question 1

What is Data Validation

Answer 1

Ensures that the data entered by the user is of a sensible nature/reasonable/valid

Question 2

Types of Data Validation

Answer 2

Data Type Check
Length Check
Range Check
Format Check
Presence Check

Question 3

Explain Range Check

Answer 3

Ensures data is in a specific range
Has a upper and lower limit

Question 4

Example of Range Check

Answer 4

A Persons month of birth should be in the range
1 Jan to 12 Dec
(lower limit) (Upper Limit)

Question 5

Explain Presence Check

Answer 5

Ensures data is present or not null

Question 6

Explain Data Type Check

Answer 6

Ensures Data is the correct data type

Question 7

Explain Format Check

Answer 7

Ensures data matches a pre-determined pattern
E.g postcode

Question 8

Explain Length Check

Answer 8

Ensures Correct number of characters are entered

Question 9

What is a table

Answer 9

A table consists of a number of records

Question 10

What is a record

Answer 10

A record is represented as a row in table

Question 11

What is a field?

Answer 11

A field is a part of a record that stores a single data item represented by a column

Question 12

What is a key field

Answer 12

A key field uniquely identifies one record

Question 13

What is a Query

Answer 13

A query searches and filters data in the database and satisfies the query criteria

Question 14

What are Forms?

Answer 14

Forms are used to collect data to create a new record, modify an existing record or view records already stored in a table

Question 15

What are Reports

Answer 15

Reports are used to present results from queries in an effective manner

Question 16

What are Macros

Answer 16

A small program written to perform a repetitive task automatically

Question 17

What are Database Relationships

Answer 17

Database relationships link two or more tables in a database using a relationship type

Question 18

What are the different types of relationships

Answer 18

One to One
One to Many
Many to Many

Question 19

What is a foreign key

Answer 19

The key field in one table is stored in another table’s non key field

Question 20

What is Big Data

Answer 20

Big Data refers to large amounts of data that have potential to be mined for information

Question 21

Explain Volume

Answer 21

Refers to the amount of data stored by organisations and how old computers wouldn’t be able to process it
Measured in Terabytes

Question 22

Explain Variety

Answer 22

Refers to the different types and varieties of data and can be stored in many formats such as video and audio not just text

Question 23

Explain Velocity

Answer 23

Refers to a speed in at which data can be processed
Due to large volumes of data, there is a need to use more powerful computers to process the data more quickly

Question 24

Explain Data Analytics

Answer 24

Data analytics involves analysing large volumes of data to produce useful information

Benificial for organisations to make descisions