Assignment 2: Database Systems & Database Models

Assignment 2: Database Systems & Database ModelsBrian Nance

CIS 515 Strategic Planning for Database SystemsStrayer University

Prof. (Dr.) Mark O AfolabiOctober 28, 2014

Assignment 2: Database Systems & Database Models 2

1. Query to determine the commission paid to specific employees

in the month of December

After information is gathered about the employee; most of what

was mentioned before, and input into the system a query can be

designed to pull that information from the tables. In order to

pull information from tables the SELECT function is used to

determine the information that is needed and the FROM function

tells from what tables to pull it (Coronel, Morris & Rob, 2012).

The coding that was used to find information on commissions paid

to employees was: SELECT Employee.*

FROM Employee, Invoice

WHERE (Department ID =2);

The asterisk next to employees indicates that all the information

under the employee table was used to generate the search. In this

query information was pulled from the employee and invoice


tables. The WHERE function more specifically states the

department which can be changed

and it would generate new information. The query currently only

shows employee commission information for employees who work in

department two.

SET LIN 250;

COLUMN "Commission Paid" FORMAT $99,990.00

SELECT e.EmpNumber, e.EmpLastName, i.InvNumber, i.InvDate,

e.CommissionRate ||'%' as "Commission Rate",

((e.CommissionRate/100)*i.InvAmount) as

"Commission Paid"

FROM Employee2 e, Invoice2 i

WHERE e.EmpNumber = i.EmpNumber

AND i.InvDate >= '01-DEC-12'

AND i.InvDate <='31-DEC-12';

2. Query for total compensation paid to each employee for the

same month

If the finance department wanted to find the total compensation

paid to each employee in the same month as the first query a


slightly different query would be run to generate that

information. The first code simply pulled the information and did

not include and computation because the finance department only

requested to be able to determine as in pull up the record for

employee’s commission paid. The second code will include

computation which will divide the yearly salary by twelve months

then multiples the commission rate by the total amount of product

sold and lastly add those two numbers together to get the total

compensation for that month.

SELECT Employee.EmpNumber, Employee.EmpFirstName,

Employee.EmpLastName, Employee.YrlySalary, Invoice.InvAmount,

Invoice.InvDate, Employee.CommissionRate

FROM Employee INNER JOIN Invoice ON Employee.EmpNumber =

Invoice.EmpNumber

WHERE (Department ID=2);

SELECT e.EmpNumber, e.EmpLastName, e.EmpFirstName,

((e.YrlySalary/12) + (e.CommissionRate/100)*i.InvAmount) as "Dec

Compensation"

FROM Employee2 e, Invoice2 i


WHERE e.EmpNumber = i.EmpNumber

AND i.InvDate >= '01-DEC-12'

AND i.InvDate <='31-DEC-12'

UNION

SELECT EmpNumber, EmpLastName, EmpFirstName, (YrlySalary/14) as

"Dec Compensation"

FROM Employee2

WHERE DepartmentId <> 10;

3. Factors necessary to ensure Referential Integrity

Coronel, Morris, and Rob (2013) stated that, “foreign keys are

used to ensure referential integrity, the condition in which

every reference to an entity instance by another entity instance

is valid” (Coronel, Morris, & Rob, 2012). Factors necessary to

ensure referential integrity do describe a condition where a

foreign key value has a match in a corresponding table or in

which the foreign key value is null. The null foreign key value

makes it possible not to have a matching value, but the

corresponding condition on values that are not null makes it

impossible not to have a valid value. This means that, any


foreign key that contains a value ensures that the value refers

to an existing valid row in another relation. Furthermore,

referential integrity is a safeguard that makes it impossible to

assign a non-existing foreign key value to a table.

4. Entity Relationships

The Entity Relationship model, as stated by Coronel et al, (2013)

“represent the conceptual database as viewed by end user”

(Coronel et al, 2013). Entity Relationship Diagrams are a major

data modeling tool that helps organize data into entities and

define the relationships between the entities. This process

facilitates a good database structure that enables efficiency in

data storage, retrieval, and manipulation.

Relationship between entities is symbolized by lines that connect

the primary key in the parent entity to its resultant foreign key

in a child entity. Descriptors and types of the relationships are

also depicted with 1:1, 1: M or M: 1. Entity relationships in

this scenario are mostly 1:1 and two 1: M or M: 1 to denote which

connectivity describes the relationship classification.


6. Big Data in Productivity and Forecasting

Big Data could be used to assist in productivity and forecasting

of organizations product and resources because it takes “large

pools of data that can be brought together and analyzed to

discern patterns and make better decisions”. It “enhances

productivity and creates significant value for the world economy

by reducing waste and increasing the quality of products and

services (Mcguire, 2012). Additionally, Big Data adds “value by

making information transparent... “store more transactional data

in digital form”, and develop the next generation of products and

services” (Mcguire, 2012). That last aspect of Big Data allows

“manufacturers are using data obtained from sensors embedded in

products to create innovative after-sales service offerings such

as proactive maintenance to avoid failures in new products

(Mcguire, 2012).

Figure1. Shows the entity relationships between the objects and

highlights the types of relationship.


EM PLOYEE2

DEPARTM ENT2

JOB2

INVOICE2 PRODUCT2

INVOICELINE2

EM PNUM BERPK

DEPARTM ENTID FK

JOBID FK

DEPARTM ENTIDPK

JOBIDPK

INVNUM BERPK

EM PNUM BERFK

PRODUCTNUM BERPK

INVLINENUM BERPK

INVNUM BER FK

PRODUCTIDFK

Can Generate

Can Have

Belongs to

DEPARTM ENTDESCRIPTION

INVAM OUNT

PRODUCTCOST

JOBDESCRIPTION

EM PFIRSTNAM E

EM PLASTNAM E

COM M ISSIONRATE

YRLYSALARY

PRODUCTCOST

1:M

1:M

PRODUCTDESCRIPTION

1:1

1:1

1:1

1:1

Can Have

Can Generate

1:1

1:M

1:1

1:1

attribute name

attribute name

Figure 2. Data set created

Figure 3. December commission for the sale Department


Figure 4. Total compensation for December


References

Coronel, C., Morris, S., & Rob, P. (2013). Database Systems:

Design, Implementation, and Management. Mason, OH: Cengage

Learning.

Halper, F. (2012). Four Vendor Views on Big Data and Big Data

Analytics: IBM. Retrieved from:

http://fbhalper.wordpress.com/2012/01/30/four-vendor-views-

on-big-data-and-big-data-analytics-ibm/

Manyika, J., Chui, M., Brown, B., Bughin, J., Dobbs, R.,

Roxburgh, C., Byers A. (2011). Big data: The next frontier

for innovation, competition, and productivity.

http://www.mckinsey.com/insights/business_technology/big_data

_the_next_frontier_for_innovation

Mcguire, T. (2012, July). Why big data is the new competitive

advantage. Retrieved from

http://www.iveybusinessjournal.com/topics/strategy/why-big-

data-is-the-new-competitive-advantage

Assignment 2: Database Systems & Database Models

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