INFS2200/7903 PROJECT ASSIGNMENT
Semester Two 2019


Marks: 100 marks (15%)
Due Date: 11:59PM 20-October-2019
What to Submit: SQL script file in addition to a short report
Where to Submit: Electronic submission via Blackboard


The goal of this project is to gain practical experience in applying several database
management concepts and techniques using the Oracle DBMS.

Your main task is to first populate your database with appropriate data, then design,
implement, and test the appropriate queries to perform the tasks explained in the next
sections.

You must work on this project individually. Academic integrity policies apply. Please
refer to 3.60.04 Student Integrity and Misconduct of the University Policy for more
information.

Roadmap: Section 1 describes the database schema for your project and it also
provides instructions on downloading the script file needed to create and populate your
database. Section 2 describes the tasks to be completed for this project. Finally,
Section 3 provides you with all the necessary submission guidelines.

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SECTION 1. THE SALES DATABASE

The Database: The SALES database (Figure 1) captures the sales information in a
company that provides IT services. The database includes four tables: CLIENT,
PURCHASE, EMP, and DEPT. CLIENT stores information about all the company’s
clients. PURCHASE keeps track of the service purchases made by the clients. EMP
stores information about the employees who work directly with the clients and serve
their purchase requests. Employees work in different departments and the information
about these departments is stored in the DEPT table. Figure 1 presents the database
schema.






















Figure 1 Database schema


The Script File: Please go to Blackboard and download the supplementary script file
for this project “prjScript.sql”.

EMP

EmpNo
EName
Position
DeptNo
PURCHASE

PurchaseNo
ReceiptNo
ServiceType
PaymentType
GST
Amount
ServedBy
ClientNo
CLIENT

ClientNo
CName
Phone
DEPT

DeptNo
DName

The Database Constraints: The following table lists all the constraints applied to the
SALES database.

No Constraint Name Table.Column Description
1 PK_EMPNO EMP.EmpNo EmpNo is the primary key of
EMP
2 PK_DEPTNO DEPT.DeptNo DeptNo is the primary key of
DEPT
3 PK_PURCHASENO PURCHASE.PurchaseNo PurchaseNo is the primary
key of PURCHASE
4 PK_CLIENTNO CLIENT.ClientNo ClientNo is the primary key
of CLIENT
5 UN_DNAME DEPT.DName DName values are unique
6 CK_AMOUNT PURCHASE.Amount Amount (in dollars) must not
be empty (not null)
7 CK_ENAME EMP.EName EName must not be empty
(not null)
8 CK_DNAME DEPT.DName DName must not be empty
(not null)
9 CK_CNAME CLIENT.CName CName must not be empty
(not null)
10 CK_RECEIPTNO PURCHASE.ReceiptNo ReceiptNo must not be
empty (not null)
11 CK_SERVICETYPE PURCHASE.ServiceType Service type must be one
of the following: 'Training',
'Data Recovery',
'Consultation', 'Software
Installation', or 'Software
Repair'
12 CK_PAYMENTTYPE PURCHASE.
PaymentType
Payment type must be one of
the following: 'Debit', 'Cash',
or 'Credit'
13 CK_GST PURCHASE.GST GST must be either 'Yes' or
'No'
14 FK_DEPTNO EMP.DeptNo and
DEPT.DeptNo
EMP.DeptNo refers to
DEPT.DeptNo
15 FK_EMPNO PURCHASE.ServedBy
and EMP.EmpNo
PURCHASE.ServedBy refers
to EMP.EmpNo
16 FK_CLIENTNO PURCHASE.ClientNo
and CLIENT.ClientNo
PURCHASE.ClientNo refers
to CLIENT.ClientNo

Table 1. Database constraints

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SECTION 2. ASSIGNMENT TASKS


Create and Populate Database: You need to execute the script file “prjScript.sql” to
create and populate your database before working on the following tasks. Wait till you
see the message “Commit complete.” It should only take several seconds. The script
will also drop related tables.


Task 1 – Constraints

1. After running the script file, you will notice that only some of the constraints
given in Table 1 were created. Write the necessary SQL statements to find out
which constraints have been created on the tables EMP, DEPT, PURCHASE,
and CLIENT.

2. Write the necessary SQL statements to create all the missing constraints.


Task 2 – Triggers

1. Write a SQL statement to find the company’s top client. A top client is the one
who has purchased the most (i.e., the one with the highest total purchase
amount (in dollars) among all the company’s clients). Your statement should
display: client number, client name, and the total purchase amount by that client.

2. Write a SQL statement to create an Oracle trigger called TOP_DISCOUNT that
applies a 15% discount to any future purchases made by the top client found in
Task 2.1.

Hint: Your trigger should use the value obtained from Task 2.1. In particular, it
should apply 15% reduction to the purchase amount whenever a new purchase
made by that top client is inserted into the PURCHASE table.

3. The ‘SALES - Sunshine’ department has unfortunately run into a technical issue
and is temporarily unable to process any ‘Credit’ or ‘Debit’ transactions. As a
result, it only accepts ‘Cash’ transactions. Besides, the department is offering
a 30% discount on ‘Data Recovery’ at the moment. Write a SQL statement to
create an Oracle trigger SUNSHINE_DEPT that will set the PaymentType to
always be ‘Cash’ for any purchases where the client is served by an employee
of this department, and if the ServiceType is ‘Data Recovery’, give the customer
a 30% discount. Note that this discount is exclusive to the ‘SALES - Sunshine’
department.


Task 3 – Views

1. Write a SQL statement to create a (virtual) view called V_DEPT_AMOUNT that
lists the DeptNo and DName of all the company departments together with the
maximum, minimum, average, and total purchase amount contributed by each
of those departments.

2. Write a SQL statement to create a materialized view MV_DEPT_AMOUNT that
lists the same information as in Task 3.1.

3. Execute the following two SQL statements and report their query execution time.
Did the materialized view speed up query processing? (Hint: Look at both the
elapsed time and the cost in the execution plan)? Explain your answer.

Q1: SELECT * FROM V_DEPT_AMOUNT;
Q2: SELECT * FROM MV_DEPT_AMOUNT;

4. Write SQL statements to create a virtual view called V_DEPT_EMP_AMOUNT
and a materialized view called MV_DEPT_EMP_AMOUNT respectively. These
views should report the contribution of each employee in each department. In
particular, for each employee, the view should list: EmpNo, the total number of
purchases, the average amount of purchases, the largest amount of purchase,
and the total amount of purchases served by that employee. The view should
list the departments in increasing order of DeptNo, and within each department
the employees should be listed in decreasing order of the total amount of
purchases.

5. Execute the following two SQL statements and report their query execution time.
Did the materialized view speed up query processing? (Hint: Look at both the
elapsed time and the cost in the execution plan)? Explain your answer.

Q3: SELECT * FROM V_DEPT_EMP_AMOUNT;
Q4: SELECT * FROM MV_DEPT_EMP_AMOUNT;


Task 4 – Indexes

1. Each receipt is issued from a receipt book whose number is encoded in the first
three digits of the ReceiptNo field in the PURCHASE table. For example, the
receipt numbered 454333 was issued from receipt book number 454. Write a
SQL statement to count the number of purchases for which there have been at
least 10 other purchases issued from the same receipt book.

Hint: For each purchase p in the PURCHASE table, you will need to go over
all the other purchases and find the ones with a ReceiptNo that starts with the
same 3 digits as in p’s ReceiptNo.

2. In order to speed up the query in Task 4.1, a function-based index is to be
created on the ReceiptNo field. Write a SQL statement to create an index called
BOOK_INDEX that best fits the task and justify your choice. Report execution
time of the query statement you wrote in Task 4.1 before and after creating this
index. Did the index speed up the query (Hint: Look at both the elapsed time
and the cost in the execution plan)? Explain your answer.

3. The manager of department 50 wants to see the total amount of sales for his
department for all purchases of services that do not contain the word ‘Software’
(e.g., not ‘Software Repair’, ‘Software Installation’ or any other ServiceType
containing the word ‘Software’). Write a SQL query to return this amount.

Note: To make your query general enough, assume that Constraint #11 is not
in place and there could be many services offered by the department that are
beyond the ones listed in Constraint #11. Besides, you should avoid using LIKE
and instead use string manipulation functions such as INSTR, SUBSTR, etc.

4. In order to speed up the query in Task 4.3, a function-based index is to be
created on the ServiceType field. Write a SQL statement to create an index
called SERVICE_INDEX that best fits the task and justify your choice. Report
the execution time of the query statement you wrote in Task 4.3 before and
after creating this index. Did the index speed up the query (Hint: Look at both
the elapsed time and the cost in the execution plan)? Explain your answer.

5. Write a SQL statement to count the number of purchases for which there are at
least 1,000 other purchases with the same ServiceType, PaymentType, and
GST values.

6. In order to speed up the query in Task 4.5, indexes should be created on the
ServiceType, PaymentType, and GST columns. In your opinion, what is the
most suitable index type to create on those columns, and why? (Note: Do not
include any SQL to create these indexes in your script file; just provide your
answer in the report.)


Task 5 – Execution Plan

1. Write a SQL statement to list the information for purchase number 1234. Report
and explain the plan chosen by the Oracle optimizer for executing your query.

2. Drop the primary key constraint from the PURCHASE relation and re-execute
the query you wrote in Task 5.1. Report and explain the plan chosen by the
Oracle optimizer for executing your query. In your opinion, what are the main
differences between this plan and the one obtained in Task 5.1?


Marking Scheme:

Tasks Marks
1.1 4
1.2 6
2.1 6
2.2 6
2.3 10
3.1 4
3.2 4
3.3 4
3.4 8
3.5 4
4.1 6
4.2 8
4.3 4
4.4 6
4.5 4
4.6 4
5.1 3
5.2 4
Presentation &
Readability
5
Total 100


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SECTION 3. Deliverables

The project is due 11:59PM, 20 October 2019. Late submissions will not be accepted.

You are required to turn in two files (use studentID to name your files):

1. studentID.pdf: (rename studentID) – Submit on Blackboard via the Turnitin link
“Submission – Report Only”
A report answering all the questions in Section 2 including all the necessary
SQL statements and screenshots of their outputs.

2. studentID.sql: (rename studentID) – Submit on Blackboard via the standard
upload link “Submission – SQL Script Only”
A plaintext script file that includes all your SQL statements.

Your report file should include the following content:

• Answers to all the questions in Section 2.

• If you are asked to write SQL statements, you need to include those statements
in your report.

• When you execute a SQL statement, if Oracle produces any output (e.g. query
results, query execution time, query plan, etc), you need to include a screenshot
of the output as well. For example, in Task 2.1, you need to include a SQL
statement to find the client who purchased the most and you also need to show
a screenshot of the response of SQL*Plus when you execute that statement.
Your entire answer for Task 2.1 should look similar as below (the actual result
might be different).

SELECT … [your statement comes here]



• Note: Please be sensible when including query output. Any output close to the
size of one page can be shown by just including the first 10 lines and the last
10 lines. Reports including pages of a query output will lose presentation marks.
You may find some helpful instructions for formatting query output in Practical
2 or the following Oracle documentation:

https://docs.oracle.com/cd/A57673_01/DOC/server/doc/SP33/ch4.htm


Your script file is in plain text format. You must make sure that your script file can be
executed on the ITEE lab machines by the “@” command. The same SQL statements
in your script file should also be copied and pasted into your report file (as explained
above). Even though the script file does not introduce any new information compared
to the report, it is intended to help the lecturer/tutors to quickly check the correctness
of your SQL statements before checking the details in your report file.