1. GCSE COMPUTER SCIENCE
Data
2.4 Databases & SQL

2. Are used to store structured data.
Structured & Unstructured Data
You need to be able to name some examples of structured and unstructured data.
Unstructured Data
Photos
Presentations
Videos
Documents
Structured Data
Phone Book
Address Book
Customer Details
Train Timetable
Databases
Are used to store structured data.

3. Key Terms Field One piece of information. Record
All of the data or information about one item.
Primary Key
A unique identity for each record.
Table
Stores all of the information about one particular category.
Student_ID
First_Name
Last_Name
Address
DOB
Gender 1
Peter
James
310 Brook Lane
21/05/1985
Male 2
Tony
Jackson
7 Somerset Avenue
15/12/1992 3
Sarah
Jones
35 West End Road
6/08/1980
Female
ACTIVITY
Write the three key definitions in your exercise book.

4. Activity 1
Can you find an example in this database showing a primary key, field, record and table?
Primary Key ID
Name
Breed
Gender
Date_Of_Birth
Enclosure
Capacity
Headkeeper
C009
Toni
Tiger
Male
30/6/1982
Big Cats 12
J Milner
C015
Andrew
Lion
Female
18/6/2009
A007
Chimpy
Chimpanzee
19/7/2011
Ape House 50
S Larkin
Record
Table
Field

5. Turn the A4 sheet into a revision poster by:
Activity 2
Instructions
Cut out the table and stick it in the middle of a page in your book.
Write in the elements and group them to form records for each video game.
Turn the A4 sheet into a revision poster by:
Adding ‘Databases’ as the title
Labelling the primary key and writing a short definition of the term.
Labelling a field and writing a short definition of the term.
Labelling a record and writing a short definition of the term.
Labelling the table and writing a short definition of the term.

6. Correct Groups Game ID Title Platform Genre Release Date 01 Pacman
Arcade
1980 02
Halo
Xbox
First Person Shooter
2001 03
Minecraft PC
Survival
2009 04
Wii Sports
Wii
Sports
2006 05
Super Mario Bros.
NES
1985

7. Write this in formation about relational databases in your book.
Relational Databases split data across different tables to reduce duplication.
A foreign key is used to link tables together and create a relationship between them.
Student_ID
First_Name
Last_Name
Address
DOB
Gender
Class_ID
Student_ID
Subject
Teacher_ID
A foreign key is a field in one table that is linked to a primary key in another table.
ACTIVITY
Write this in formation about relational databases in your book.

8. Activity 3
How could this table be split into two linked tables called Animal and Enclosure? Write down the field names that should go in each table. ID
Name
Breed
Gender
Date_Of_Birth
Enclosure
Capacity
Headkeeper
C009
Terry
Lion
Male
30/6/1982
Big Cats 12
J Milner
A019
Sam
Gibbon
Female
10/6/2002
Ape House 50
S Larkin
C015
Toni
Tiger
18/6/2009
B033
Bob
Red deer
6/7/2007
Deer Park
200
A Hunt
A007
Charlie
Chimpanzee
19/7/2011
ANSWER
ANIMAL Table: ID, Name Breed, Gender Date_of_Birth, Enclosure.
ENCLOSURE Table: Enclosure, Capacity, Headkeeper.

9. Activity 4
Re-organise the data from the Zoo table in Activity 2 in to two linked tables called Animal and Enclosure.

10. Activity 4 Answer ID Name Breed Gender Date_of_Birth Enclosure C009
Terry
Lion
Male
30/6/1982
Big Cats
A019
Sam
Gibbon
Female
10/6/2002
Ape House
C015
Toni
Tiger
18/6/2009
B033
Bob
Red Deer
6/7/2007
Deer Park
A007
Charlie
Chimpanzee
19/7/2011
Enclosure
Capacity
Headkeeper
Big Cats 12
J Milner
Deer Park 50
S Larkin
Ape House
200
A Hunt

11. SQL = < > <= >= <>
Structured Query Language is the language used to search databases. You need to be able to read and write simple SQL statements.
The following comparison operators are used in SQL statements:
Comparison operator
Symbol
Equal to =
Less than
<
Greater than
>
Less than or equal to
<=
Greater than or equal to
>=
Not equal to
<>
Apart from equal to and not equal to they are the same as Python.

12. Here is an example SQL statement
SQL Statements
Here is an example SQL statement
SELECT First_Name from Student WHERE Gender=“Male”
Fields to show
The table
Search criteria
This statement selects the First_Name from the Student table and only shows the Male students.
Student_ID
First_Name
Last_Name
Address
DOB
Gender 1
John
Curtis
12 Brook Lane
21/03/1990
Male 2
Ben
Jackson
1 Totters Lane
15/04/1990 3
Sarah
Smith
60 Belsize Rd
6/06/1990
Female
First_Name
John
Ben

13. SQL Commands Command Description Deletes rows from a database table.
DELETE FROM TableName
WHERE condtion
Deletes rows from a database table.
CREATE TABLE TableName
(FieldName data type, …)
Creates a database table.
INSERT INTO TableName
VALUES (Value, …)
Inserts row into a database table.
SELECT (FieldName, …)
FROM TableName
WHERE condition
ORDER BY (FieldName, ..)
Retrieves data from a table.
The asterisk (*) can be used if all columns are required in the output.
FROM Table1Name, Table2Name, …
WHERE join criteria
Retrieves data from two related tables.
UPDATE TableName
SET (FieldName=Value, …)
Updates rows in a database table.

14. Included in search results Not included in search results
SQL Practical: Instructions
Several volunteers are needed!
Each of you is a record in a database called Students. For each query displayed you will go to one side of the room. Go to the left if your record would be included in the query results and to the right if your record wouldn’t be included in the query results.
Included in search results
Not included in search results

15. Included in search results Not included in search results
SQL Practical
Included in search results
QUERY 1
Not included in search results
SELECT *
FROM Students

16. SQL Practical SELECT * FROM Students WHERE HairColour = “Blond”
Included in search results
QUERY 2
Not included in search results
SELECT *
FROM Students
WHERE HairColour = “Blond”

17. SQL Practical SELECT * FROM Students WHERE EyeColour = “Blue”
Included in search results
QUERY 3
Not included in search results
SELECT *
FROM Students
WHERE EyeColour = “Blue”

18. SQL Practical SELECT * FROM Students WHERE EyeColour = “Brown”
Included in search results
QUERY 4
Not included in search results
SELECT *
FROM Students
WHERE EyeColour = “Brown”
ORDER BY FirstName

19. Included in search results Not included in search results
SQL Practical
Included in search results
QUERY 5
Not included in search results
SELECT *
FROM Students
WHERE BirthMonth > 7
ORDER BY Height

20. SQL Practical SELECT * FROM Students WHERE BirthMonth <= 5
Included in search results
QUERY 6
Not included in search results
SELECT *
FROM Students
WHERE BirthMonth <= 5
ORDER BY FirstName DESC

21. SQL Practical SELECT * FROM Students
Included in search results
QUERY 7
Not included in search results
SELECT *
FROM Students
WHERE HairColour = “Brown” or HairColour = “Black”
ORDER BY FirstName DESC

22. SQL Practical SELECT * FROM Students
Included in search results
QUERY 8
Not included in search results
SELECT *
FROM Students
WHERE HairColour = “Black” and EyeColour = “Brown”
ORDER BY LastName DESC

23. Link: https://www.codeschool.com/courses/try-sql
Activity 5
Sign up for a free Code School account and complete the Try SQL course.
Link:

24. Use this table to help you answer the following activities.
Marksheet Table
TABLE 1
Use this table to help you answer the following activities.
Name
Assign1
Assign2
Assign3
Average
Aisha 51 60 64 58
Katharine 75 76 48 70
Fiona
100 87 72 86
Gareth 65 69 73 Jo 38 52 44 45
Manjit 66 68
Ian 13 17 26 19
Michael 43 33 40
Ubaid 55 50 53
Simon
Mark 25 15
Gemma 78

25. Activity 6 Question Answer v v v v USE TABLE 1
SELECT Name FROM Marksheet WHERE Assign1=0
Mark
SELECT Name FROM Marksheet WHERE Assign1>80
Fiona
Gareth
SELECT Name , Average FROM Marksheet WHERE Assign1<=30
Ian, 19
Mark, 13
Display the Name and Average of all the students that scored 60 or above in Assign3.
SELECT Name, Average FROM Marksheet WHERE Assign3 >= 60
Display the Name and Average of all the students that scored less than 40 Assign2.
SELECT Name, Average FROM Marksheet WHERE Assign2 < 40
Display the Name and Average of all the students that did not score 40 in Assign1.
SELECT Name, Average FROM Marksheet WHERE Assign1 <> 40 v v v v
USE TABLE 1

26. Use this table to help you answer the following activities.
Food_Item Table
TABLE 2
Use this table to help you answer the following activities.
Product_Code
Product_Name
Price
Supplier_Code
Quantity_In_Stock
1239T
Baked beans
0.34
S121/A
154
1237T
Tomato soup
0.56
450
1309T
Spaghetti hoops
0.80 99
4550F
Oven chips
1.24
S234/F
550
3444F
Fish fingers
1.45
756
2121G
Frankfurters
1.02
S009/C 52
5544C
Sausage rolls
2.45
S100/C
150

27. Search (also called a Query)
Activity 7
Task
Search (also called a Query)
Write the SQL command to insert a new record into Products table, for a product with these details:
Product_Code: 5500C
Product_Name: Pork pie
Price: 2.45
Supplier_Code: S100/C
Stock: 150
INSERT INTO Products VALUES (5500C, Pork pie, 2.45, S100/C, 150)
Write the SQL command to update the record for Tomato soup, the Quantity_In_Stock is now 415.
UPDATE Products
SET (Quantity_In_Stock = 415)
Write the SQL command to delete the Oven chips record from the Food_Item Table.
DELETE FROM Products
WHERE (Product_name = Oven chips)
Write the SQL command to delete one more record of your choice from the Food_Item Table. v v v
USE TABLE 2

28. puzzle maker criss-cross
Activity 8
Crossword
Create a crossword based on this topic using the online crossword generator linked below. It should have a minimum of 10 questions.
When you have finished, paste your crossword on to a Powerpoint slide and name it Databases & SQL.
Print out one copy (include your name) and stick it in your book.
puzzle maker criss-cross