Introduction

INTRODUCTION

Module 2:1

Introduction

Data Model Building Blocks

Business Rules

Translating Business Rules to Data Models

Summary

• Both my great grandparents had 2 children each. My Father had 4 siblings with 3 children each. My Mother had 3 siblings with 2 children each. My Father had 2 other Cousins with 2 children each. My Mother had 2 cousins with 3 children each. We are 5 in my family

Introduction


Business Rules


Summary

• How many 1st degree cousins do I have? 2nd degree? How many cousins do we have in the whole clan? Great grand children?

• Given that all my titos and titas will give my 500 for christmas, how many will I receive by the 26th?

• How many are we all in all?

Introduction


Business Rules


Summary

• Solve for all cousins:Father Side

Father siblings = 4 x 3 children each = 12Father cousin = 2 x 2 children each = 4Father side = Father sibling + Father cousinFather side = 16 children

Mother SideMother sibling = 3 x 2 children each = 6 Mother cousin = 2 x 3 children each = 6Mother side = Mother sibling + Mother cousinMother side = 12

Cousins = Motherside + Fatherside = 16+12 = 28

Introduction


Business Rules


Summary

• Solve for all greatgrandchildren:Since Father Side = 16 and Mother Side =12And FatherMotherchildren = 5 childrenFS+MS+FMC= 16+12+5 = 33

• Solve for Titostitas:Fatherside:

Let FGGParents = (FGParentsA + FGParentsB) x 2FGParentsA= 2 ; FGParentsB = 4FGGParents = (2+4)2 = 12

MothersideMGGParents = (MGParentsA + MGParentsB) x 2MGParentsA= 2 ; FGParentsB = 3MGGParents = (2+3)2= 10

Christmas_Aguinaldo=(Motherside+Fatherside)xP500Christmas_aguinaldo=(10+12)x500=(22)xP500)=11,000

Introduction


Business Rules


Summary

• How many are we all in allSince all siblings = 33Titos and Titas = 22Grandparents = 2 x 2 = 4 x 2 = 8Great grand parents = 2 x 2 = 4Parents = 2

• Allinall=33+22+8+4+2= 69

Introduction


Business Rules


Summary

Introduction


Business Rules


Summary

• Data models…Relatively simple representationsUsually graphicalOf a more complex real-world data structure

• …supported by powerful database design tools have made it possible to substantially diminish the errors of database design.

Introduction


Business Rules


Summary

• help understand the complexities of a real-world object or event

• It represents data structures and their:

CharacteristicsRelationsConstrainsTransformations

BUILDING BLOCKS OF DATA MODELS

Module 2:1

Introduction


Business Rules


Summary

• 1950s and early 1960s:Data processing using magnetic tapes for storage

Tapes provide only sequential accessPunched cards for input

• Late 1960s and 1970s:Hard disks allow direct access to dataNetwork and hierarchical data models in widespread useTed Codd defines the relational data model

Would win the ACM Turing Award for this workIBM Research begins System R prototypeUC Berkeley begins Ingres prototype

High-performance (for the era) transaction processing

Introduction


Business Rules


Summary

• 1980s:Research relational prototypes evolve into commercial systems

SQL becomes industry standardParallel and distributed database systemsObject-oriented database systems

• 1990s:Large decision support and data-mining applicationsLarge multi-terabyte data warehousesEmergence of Web commerce

• 2000s:XML and XQuery standardsAutomated database administrationIncreasing use of highly parallel database systemsWeb-scale distributed data storage systems

Introduction


Business Rules


Summary

• A collection of tools for describing

Data entitiesData attributesData relationshipsData constraints

Introduction


Business Rules


Summary

• Anything! Person, Place or thing, or events which data are to be collected and stored

• An entity represents a particular type of object in a real world

Physical objectscustomersProducts

Introduction


Business Rules


Summary

• Characteristics of an entity

• Example: the Attributes of a Customer are:

FirstnameLastnameCourseYear

Introduction


Business Rules


Summary

• Association among entities• Example:

The relationship between customers and an agent

• Types of RelationshipOne to Many (1:M) relationshipMany to Many (M:N) relationshipOne to One (1:1) relationship

Introduction


Business Rules


Summary

• 1:Many (1:M)Store Employees

• Many:Many (M:N)Employees Skills

• 1:1 (1:1)Employee Store

Introduction


Business Rules


Summary

• Models an enterprise as a collection of entities and relationships

Entity: a “thing” or “object” in the enterprise that is distinguishable from other objects

Described by a set of attributesRelationship: an association among several entities

• Represented diagrammatically by an entity-relationship diagram:

Introduction


Business Rules


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Introduction


Business Rules


Summary

Painter

paints

Painting

Employee

learns

skills

Employee

manages

store

1 1

1M

M

N

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Business Rules


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• Example of tabular data in the relational model

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Business Rules


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Introduction


Business Rules


Summary

• Restrictions placed on the data

• This ensures data integrity• Usually in a form of rulews• Examples

QPI: Not less than 0.00 not more than 4.00A class should only have a maximum of 45 studentsA teacher should only have 21 units or 7 subjectsAn uyab should have one and only one uyab.

Introduction


Business Rules


Summary

• Physical level: describes how a record (e.g., customer) is stored.

• Logical level: describes data stored in database, and the relationships among the data.

type customer = recordcustomer_id : string; customer_name : string;customer_street : string;customer_city : string;

end;

• View level: application programs hide details of data types. Views can also hide information (such as an employee’s salary) for security purposes.

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Business Rules


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• An architecture for a database system

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Business Rules


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BUSINESS RULES

Module 2:1

Introduction


Business Rules


Summary

• Before database designers start designing databases (entities, attributes and relationships), they understand first the business rules.

Introduction


Business Rules


Summary

• A business rule isBriefPreciseAnd unambiguous

• Description of PoliciesProceduresAnd principles

• Of a specific organization

Introduction


Business Rules


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• Business rules help to create and enforce action within that organization’s environment

• It is rendered in writing and updated to reflect any changes in the organization’s operational environment

Introduction


Business Rules


Summary

• A customer may generate many invoices

• An invoice is generated by one customer

• A training session cannot be scheduled for fewer that 10 employees or for more than 30 employees.

Introduction


Business Rules


Summary

• A customer may generate many invoices(1:M relationship)

• An invoice is generated by one customer(1:M relationship)

• A training session cannot be scheduled for fewer that 10 employees or for more than 30 employees.(1:M relationship with a constrain)

TRANSLATING BUSINESS RULES INTO DATA MODEL COMPONENTS

Module 2:1

Introduction


Business Rules


Summary

• What are the Business Rules? Site all of it.

• In every business rule, look for its entities and attributes

• Are there relationships from it?

• From the business rules, identify possible constrains.

Introduction


Business Rules


Summary

• Enrolling a Subject IM32Business Rules

A class should have a maximum of 45 studentsA student can’t enroll twice on a class on the same semester.There should be one teacher per class.Only 3rd and 4th year IM students are allowed to enroll in the class

Introduction


Business Rules


Summary

• Enrolling a Subject IM32Entities

ClassStudentTeacher

Introduction


Business Rules


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• Enrolling a Subject IM32Attributes

Class Seats, Subject Code,Subject Description,Schedule

StudentName, year, course

TeacherName, Subject, Schedule

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Business Rules


Summary

• Enrolling a Subject IM32Constrains

Class not exceed 45 studentsTeacher not exceed 45 students

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Business Rules


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• Enrolling a Subject IM32Relationships

Class1 Class 1 Teacher1 Class 45 students

Student1 Student 1 Class

Teacher1 Teacher Many students1 Teacher 1 Class1 Teacher 1 Class schedule

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Business Rules


Summary

Class

enrols

student

Teacher

teaches

skills

Teacher

handles

Class

1 1

1M

M

N

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SUMMARY

Module 2:1

Introduction


Business Rules


Summary

• Data Model is a (relatively) simple abstraction of complex real-world data environment. Database designers ause data models to communicate with application programmers and end users.

Introduction


Business Rules


Summary

• Basic data-modeling components are entities, attributes , relationships and constrains

Introduction


Business Rules


Summary

• Business rules are used to identify and define the basic modeling components within a specific real-world environment

END

Module 2:1

Date post:	21-Jan-2016
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