Topic 4: Database

Question 1

What is a database

Answer 1

A database is a collection of related or structured information held on a computer (e.g. doctor’s records, school roll etc.).

Question 2

A flat file database is where all the information is stored in one table. These can be problematic as they:

Answer 2

Increase data redundancy - data is repeated unnecessarily.

 Decrease data integrity - data is unreliable as the same data is stored several times increasing the likelihood of errors.

Question 3

What is a Relational database

Answer 3

A relational database contains more than one table, and the tables are linked through common fields.

Question 4

Relation database It is the more efficient database type as it reduces (Advantages of relational databases):

Answer 4

Data redundancy is reduced data that is repeated unnecessarily is reduced.

 Data integrity is greater - data is more likely to be correct and reliable.

 Queries and Reports - can be created using more than one table.

Question 5

What is a table

Answer 5

A table consists of one or more records

Question 6

What is a record

Answer 6

A record is a collection of data items, which may be of different data types, all relating to the individual or object that the record describes

Question 7

What is a field

Answer 7

A field is part of a record designed to hold a single data item, of a specified type

Question 8

What is a primary key field

Answer 8

A key field uniquely identifies a record

Question 9

What is the foreign key

Answer 9

When the primary key from one table appears as a field in a second table, it is known as a foreign key of the second table.

Question 10

What is a composite

Answer 10

A composite key is one that consists of two or more fields.

Question 11

What is Data Validation

Answer 11

Validation is the automatic checking of data when it is entered into a computer system.

Question 12

What is a data type

Answer 12

A data type is a formal description of the kind of data being stored or manipulated within a program or system

Question 13

What is a relationship

Answer 13

The function of a relationship is to link tables.

Question 14

Advantages of having links between tables:

Answer 14

⦁ Reduces data redundancy – data that is repeated unnecessarily.
⦁ Increases data integrity - data is more likely to be correct or is reliable as the same data is not stored/entered several times decreasing the likelihood of errors.
⦁ Reports/Queries can be created using data from more than one table.
⦁ Referential integrity is enabled – this ensures data is kept consistent in the tables. For example, when data is deleted from one table, the linked data in other table(s) is also deleted.

Question 15

What is referential integrity

Answer 15

Referential integrity ensures that an entry cannot be made in one table with a foreign key, if the key field does not exist in the linked table.

Question 16

What are forms

Answer 16

: Forms are used to enter/collect data in a database

Question 17

What is a lookup list and advantages

Answer 17

a lookup list is a list of data that can be used to provide all values for a data field.

The advantages of lookup lists are:

⦁ Less chance of mistakes being made.
⦁ Increased speed of data entry so you don’t have to type the data in.
⦁ Limits entry options meaning users can only enter valid values.

Question 18

What is a query in a database

Answer 18

A query is used to retrieve selected information from a database in order to answer a question

Question 19

What is a parameter query

Answer 19

A parameter query is where the user is prompted to enter search criteria each time the query is activated.

Question 20

What is a report

Answer 20

A report is the presentation of information from a query or table in a user-friendly way

Question 21

What is import

Answer 21

Import is the ability to accept a file produced by other software and place it into the database without having to enter the data again

Question 22

What is export

Answer 22

To export is to create a data file using one piece of software so that it can be read by a different piece of software.

Question 23

What is a CSV

Answer 23

CSV – Comma Separated Variable/Value

Question 24

What is a macro

Answer 24

A macro is a small program used to perform repetitive tasks automatically.

Question 25

What is Mail Merge

Answer 25

Mail merge documents are template documents which are set up to contain merge fields.

Question 26

What is a template

Answer 26

Template is a predefined spreadsheet/ document/ layout that can be reused/used/edited/added to documents with the same formatting and formulas

Question 27

Advantages of templates

Answer 27

An advantage is that it can be re-used and edited for different purposes.

Question 28

What is a wizard program

Answer 28

A wizard is a program (or software) which helps a user complete a task using step by step instructions (using prompts).

Question 29

There is no generally agreed definition of big data, and it is not just about the size of the data sets. However, it is agreed that big data cannot be analysed by normal means (2018).

Answer 29

There is no generally agreed definition of big data, and it is not just about the size of the data sets. However, it is agreed that big data cannot be analysed by normal means (2018).

Question 30

Sources of Big Data

Answer 30

Sources of big data include (2018):

⦁ Text, images and videos uploaded to social media sites.
⦁ Medical records.
⦁ Fitness monitors.
⦁ Financial markets - share price data, currencies, etc.
⦁ Web server logs.
⦁ Mobile phone records.
⦁ E-commerce transactions.
⦁ Device logs (Internet of things).

Question 31

What is Volume

Answer 31

This is large data sets that are so complex that traditional tools, such as relational database management systems, are not able to deal with them effectively. It is the quantity of data produced

Question 32

What is velocity

Answer 32

Velocity about how fast the data is coming in; the incoming rate of data is very high and therefore the speed of data processing must be high

Question 33

What is variety

Answer 33

The data that is produced is unstructured and comes in various forms and formats. The challenge is to store the data in a structured format

Question 34

What is Data Analytics

Answer 34

Data analytics is the application of algorithms to data to identify trends. It can include statistical analysis or Artificial Intelligence. It is analysing data to draw conclusions