Mysqldbrentalgamesdb

1
MySQL Assignment April 2016
Lecturer: P. De Burca
Assignment Game Rental Shop
By David Bourke
Part 1
E.R Diagram
The Main Entities Operational Masters
Customers Customer Id
Staff Staff Id
Suppliers Game Name
Shop Stock Game Code
Rent Receipt Rent No
Over Due Rent No

2
Normalisation
UNF 1 NF 2 NF 3 NF
Store Id Store Id PK Store Id PK Store Id PK
Store Address Store Address Store Address Store Address
Customer id Title id Title id Title id
Customer name Title name Title name
Customer address Platform Platform
Title id Cost per game Cost per game
Title name
Platform Store Id PK Store Id PK Store Id PK
Cost per game Customer id PK Customer id Customer id PK
Customer name Customer name Customer name
Customer address
Customer id PK Customer id PK
Customer name Customer name
Customer address Customer address
Title Id
Title id PK
Title name
Platform
Cost per game

3
Part 3 Reports
1 Weekly transactions.
Monday is the first working day of the week.
SELECT * FROM rent_receipt
WHERE date_out BETWEEN ‘2015-04-20 AND 2015—04-26’;
2 Games and their Platform by Publisher Ref shop_stock Table
‘SELECT title, platform,publisher
FROM shop_stock
ORDER BY publisher’;

4
3 list all game which came out in 2015.
Xbox 360 games released in 2015. This is the supplier table. The table named shop_stock
Is the list of games the shop has in stock. The supplier table is a list of xbox games we can
purchase from suppliers.

5
4 List all game with release date 2015 ref shop_stock Table
SELECT title,publisher,release_date
FROM shop_stock
WHERE release_date BETWEEN ‘2015-01-01 AND 2015-12-31’;

6
5 Total all late payments for the month for the month of April 2015
‘SELECT customer _id ,title SUM(total_due) AS grand_total
FROM over_due
WHERE late_return_date BETWEEN ‘2015-04-01’ AND 2015-04-30’
GROUP BY customer_id,title;
6 Total revenues Sum rent_receipt and Sum over_due Tables
SELECT (SELECT SUM(paid) FROM rent_receipt) + (SELECT SUM(total_due) FROM over_due
FROM DUAL;

7
7 Two different methods to list all PS4 games in Stock (not currently out)
SELECT title,platform,in_stock
FROM shop_stock
WHERE in_stock = ‘y’ AND platform = ps4’;
Due to the way I designed the database games are in stock until they are booked out.
Y = yes in stock n = no not in stock. Not sure of a second method.

8
Document and Analysis
Part 4 Testing the database
My original Database was very weak with foreign Keys.
However, I was able to use this database as a dummy database and experiment identifying
issues using Primary key and Foreign Keys’
Another issue I had was how to keep track of games in and games out.
I adopted a very simple column in the Shop Stock Table All games are in Stock ‘Y’
When the game is rented out this table is changed(Updated) to ‘N’
Giving a reading of N (Not in Stock)
Therefor two tables are affected when a customer rents a game.
The rent receipt table is updated and a rent receipt no (Auto increment) is generated
And the Values are inserted.
In the shop stock table, the ‘in_stock column is also updated from ‘y’ to ‘n’
For example, game code 30 is being rented ref table shop stock
When the game is returned the in stock in the shop stock is updated to y
Game being rented out
UPDATE shop_stock SET ‘in_stock’ = ‘n’
WHERE game_id = ‘30’
Game being returned
UPDATE shop_stock SET in_stock = ‘y’
WHERE game id = ‘30’;
It would be unusual for a customer to rent more than one game and even more unusual
For different platforms.
Conclusion: Only one Title is needed in the Rent Receipt Table and Over-Due Tables.
Re The rent_receipt table. The customer books the game and pays for it.
The date out is the booking date and the date return is the expected date return.
If the game is returned after the expected date is it over due.
Then the overdue table is activated, and updated accordingly
To calculate the total of the rent receipts with no late returns
‘SELECT SUM(paid) AS total FROM rent _receipt
Regarding the customers table
I didn’t think it would be necessary to have platform as part of this table
Customers have the choice to change their platforms. If the rental shop sold platforms
Then it would be necessary to keep a record of customer’s platforms. This would lead to a
bigger database or perhaps even another database.
Online resources You tube Derek Banas and www.Stackoverflow
There is one small flaw, I didn’t use any Index, which is faster than a table scan

9
To get the total revenue
Sum of ‘paid’ column from rent receipt table and the sum of ‘total Due’ from overdue table
‘SELECT SUM(paid),(total_due) AS total FROM rent receipt AND overdue’

10
(Test Table)
Other Commands available are concat( adding two column names together) Eg
First name and last name
Inner Join
Selecting a column from different tables and combing them into a report.

11
SELECT rent_no,game_code,first_name,last_name
FROM rent_receipt, customers
WHERE customers.customer_id = rent_receipt.customer_id;
Tables concerned rent_receipt and customers
This is a very powerful way to join different colums from two tables together.
It is also possible to join three tables together.
Design Choice
In total there are six tables.
The customer Table keeps a record of customer_id (Auto Incremented) name , address and phone
Number.
Re table rent receipt. I originally had game code 1, game code 2 and game code 3
In case a customer wanted to rent more than one game a night.However I decided against this
Re Foreign Key issues referencing back to shop_stock game_code and also it would be unusual for a
customer to rent more than one game a night

12
I created a rental table where the game is booked out. This table was seperte to the rent receipt.
The game remains booked out until it is returned.i ended up deleting this table for the simple reason
Of trying to fine tune the database.Minimise data duplication.
The shop_stock table deals with the game_code,(Primary Key) title (FK),cost,publisher,in stock
And release date.
Again trying to minimise data duplication.I could have divided this table into two tables.I thought it
was better to keep as much of game information in the one table.
Supplier table.
Being a small rental shop we some games would be rented out less than others.Therefore
Having every game available in stock is not cost effective.Some games will rent more often than
others.
A report can be ran every week to show what games are being rented out
SELECT game_code,date_out
FROM rent_receipt
WHERE date_out BETWEEN ‘2015-04-20’ AND ‘2015-04-26’
GROUP BY game_code

13
I experimented with another datbase to check multiply fields.

14
I also concidered creating a table per Platform with a more complex code for example
FiFA xbox
The first game has a code of A and the second game (with the same platform) has a code of B)
Platform X Box
Game Name Code
FIFA FXA1
FIFA FXB1
Being a small rental shop a complex code system is not necessary.
A more basic (Auto_INCREMENT) is just as effective.
The staff tableis very straigh forward.
Staff_id is my Primary Key.When a game is rented, There is a field t in the rent_receipt Table to
record which member of staff made the booking.
Loyalty Card
It would have been a bonus to add in a loyalty card per customer.
It was not requested in the assignment and it would have added another Table to the Database.
It might have caused more problems than it was worth,( experience)so in the end I didn’t run with it.

Mysqldbrentalgamesdb

More Related Content

Viewers also liked (8)

Similar to Mysqldbrentalgamesdb (20)

Recently uploaded (20)

Mysqldbrentalgamesdb