GROUP MEMBERS NO. MATRIX GROUP
ELIS ERVINA BINTI SULIMAN 2012967249 CS 241 3B
ERLIA NADIA BINTI AB. MALEK 2012996329 CS 24...
CAR
MOD_CODE
CAR_VIN CAR_COLOR
CAR_YEAR
CHEN MODEL
CAR
PK CAR_VIN
MOD_CODE
CAR_YEAR
CAR_COLOR
CROW’S FOOT MODEL
BASIC SYMBOLS
TERMINOLOGY
Entity type
a collections of things, represent collection of physical things such as
person, places, event, or...
Connectivity
To describe the relationship classification
Cardinality
A constraint on the number of entities that participa...
MANY-TO-
MANY (M-N)
ONE-TO-
MANY
(1-M)
ONE-TO-
ONE (1-1)
Classification of cardinalities
 Minimum cardinality based:
 A min cardinality of 1>= (one or more) indicates a
mandator...
Summary of Cardinalities
Type of entity
Type of
attribute
Relationship
strength
Degree of
relationship
• The entity is
existence
independent
Strong
entity
• The entity is
existence
dependent
Weak
entity
Strong relationship
• Identifying
relationship
• Exist when PK of
related entity
contains PK
component of
parent entity
We...
Example
Weak relationship but strong
entity
strong relationship but weak
entity
Attribute Composite
attribute
Simple
attribute
Single
value
attribute
Multivalu
ed
attribute
Derived
attribute
Definition ...
Degree of Relationships
 Unary
Exist when an association is maintained within a single
entity.
Binary
Exist when two ent...
SPECIALIZATION/GANERALIZATION
 Concepts of specialization/generalization is associated
with special types of entities kno...
SUPERCLASS
• Entity type that have
one or more distinct
subgrouping of it
occurrences, which
must be represented
in a data...
SUPERCLASS/SUBCLASS RELATIONSHIP
 Each member of a subclass is also a member of the
superclass. In other word the entity ...
EXAMPLES
STAFF
MANAGER
SALES
PERSONNEL
SECRETARY
SUPERCLASS
SUBCLASS
ATTRIBUTE INHERITANCE
 An entity in a subclass represent the same ‘real world’
object in the superclass.
 E.g: A member ...
GENERALIZATION/SPECIALIZATION
 To make the generalization/specialization we should
identify first their distinguish chara...
GANERALIZATION SPECIALIZATION
•The process of minimizing the
differences between entities by
identifying their common
char...
CONSTRAINT ON SPECIALIZATION
OR GANERALIZATION
DISJOINTNESS CONSTRAINT COMPLETENESS CONSTRAINT
•DEF: means that the subtyp...
Staff
StaffNo(PK)
Name
Position
Salary
Branch
BranchNo(PK)
Address
Street
City
postcode
HAS
1,1 1,M
Lets assume that we ha...
Staff
StaffNo(PK)
Name
Position
Salary
Branch
BranchNo(PK)
Address
Street
City
postcode
HAS
1,1 1,M
Manager
mgStartDate
bo...
Manager
Staff_no
Salary
mgStartDate
Bonus
SalesPersonnel
Staff_no
Salary
salesArea
carAllowance
Branch
BranchNo(PK)
Addres...
Manager
Staff_no
Salary
mgStartDate
Bonus
SalesPersonnel
Staff_no
Salary
salesArea
carAllowance
Staff
StaffNo(PK)
Name
Pos...
Branch
BranchNo(PK)
Address
Street
City
postcode
Staff
StaffNo(PK)
Name
Position
Salary
has
1..1 1..*
PartTimeTemporary
ho...
Business Rule
Step for representation
 Find the entity
 Primary key
 Name the relationship of the connection among
business entity
 ...
Presentation database about ERD
Presentation database about ERD
Presentation database about ERD
Presentation database about ERD
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Presentation database about ERD

  1. 1. GROUP MEMBERS NO. MATRIX GROUP ELIS ERVINA BINTI SULIMAN 2012967249 CS 241 3B ERLIA NADIA BINTI AB. MALEK 2012996329 CS 241 3B NORA SYAMIMI BINTI KHAIRUDDIN 2012949807 CS 241 3B NORHIDAYAH BINTI ZULKEFLI 2012755781 CS224 3A
  2. 2. CAR MOD_CODE CAR_VIN CAR_COLOR CAR_YEAR CHEN MODEL CAR PK CAR_VIN MOD_CODE CAR_YEAR CAR_COLOR CROW’S FOOT MODEL
  3. 3. BASIC SYMBOLS
  4. 4. TERMINOLOGY Entity type a collections of things, represent collection of physical things such as person, places, event, or things. Attributes A property of an entity type or relationship. Each attributes has a data type that defines the kind of values and permission operation on the attributes. Relationship association among entity types, usually two-way or bidirectional. In crow’s foot notation relationship names appear on the line connecting the entity types involved in the relationship.
  5. 5. Connectivity To describe the relationship classification Cardinality A constraint on the number of entities that participate in a relationship. Has minimum and maximum cardinality for both directions of a relationship. EXAMPLE
  6. 6. MANY-TO- MANY (M-N) ONE-TO- MANY (1-M) ONE-TO- ONE (1-1)
  7. 7. Classification of cardinalities  Minimum cardinality based:  A min cardinality of 1>= (one or more) indicates a mandatory relationship which creates an existence dependent  A min cardinality of 0 indicates an optional relationship  Maximum cardinality based  A max cardinality of 1 means the relationship is single- valued or functional (in math, value 1)  1-1 (less common), 1-M (common), M-N (common).
  8. 8. Summary of Cardinalities
  9. 9. Type of entity Type of attribute Relationship strength Degree of relationship
  10. 10. • The entity is existence independent Strong entity • The entity is existence dependent Weak entity
  11. 11. Strong relationship • Identifying relationship • Exist when PK of related entity contains PK component of parent entity Weak relationship • Non-identifying relationship • Exist if PK of related entity does not contain PK component of parent entity
  12. 12. Example Weak relationship but strong entity strong relationship but weak entity
  13. 13. Attribute Composite attribute Simple attribute Single value attribute Multivalu ed attribute Derived attribute Definition Attribute that can be further subdivided to yield additional attribute Attribute that cannot be subdivided Attribute that can have only a single value Attribute that can have many value Attribute whose value is calculated from other attribute Example Address ( street, city, zip code, state) age, sex, marital status social security number, ic number level of education, car’s color An emp_age, May be found by compUting the integer value of the different between the current date and the emp_dob
  14. 14. Degree of Relationships  Unary Exist when an association is maintained within a single entity. Binary Exist when two entities are associates in a relationship.  Ternary and higher-degree relationship Three entities are associates and higher-order relationship does allow the designer some latitude regarding the semantic of a problem.
  15. 15. SPECIALIZATION/GANERALIZATION  Concepts of specialization/generalization is associated with special types of entities known as SUPERCLASSES SUBCLASSES And the process of  ATTRIBUTE INHERITANCE
  16. 16. SUPERCLASS • Entity type that have one or more distinct subgrouping of it occurrences, which must be represented in a data model SUBCLASS • A distinct subgrouping occurrences of an entity type, which must be represented in a data model.
  17. 17. SUPERCLASS/SUBCLASS RELATIONSHIP  Each member of a subclass is also a member of the superclass. In other word the entity in subclass is the same entity in superclass, but have distinct role.  It has one to one relationship( superclass/ subclass relationship)  E.g: Staff/Manager has superclass/subclass relationship.
  18. 18. EXAMPLES STAFF MANAGER SALES PERSONNEL SECRETARY SUPERCLASS SUBCLASS
  19. 19. ATTRIBUTE INHERITANCE  An entity in a subclass represent the same ‘real world’ object in the superclass.  E.g: A member of the SALES PERSONAL inherit all the attribute of the STAFF superclass such as (staffno, name, position, salary) and together with those sales PERSONAL SUBCLASS (sales area,car allowance)
  20. 20. GENERALIZATION/SPECIALIZATION  To make the generalization/specialization we should identify first their distinguish characteristics and common characteristics for the attribute that we want to make generalization.  Hence, when we know both of them we can separate the attribute that have common characteristic in superclass while their different characteristic in every subclass.
  21. 21. GANERALIZATION SPECIALIZATION •The process of minimizing the differences between entities by identifying their common characteristic. •The process of maximizing the difference between members of entity by identifying their distinguishing characteristic. •The bottom-up process of identifying a higher level, more generic entity superclass from lower level entity subclass. •The top-down process of identifying lower level, more specific entity subtype from a higher level entity super type.
  22. 22. CONSTRAINT ON SPECIALIZATION OR GANERALIZATION DISJOINTNESS CONSTRAINT COMPLETENESS CONSTRAINT •DEF: means that the subtypes in a generalization hierarchy do not have any entities in common •DEF: means that every entity of super type must be an entity in one of the subtypes •It can be symbolized by : D •It can be symbolized by: C
  23. 23. Staff StaffNo(PK) Name Position Salary Branch BranchNo(PK) Address Street City postcode HAS 1,1 1,M Lets assume that we have this entity type. For the position attribute (STAFF)it will have manager, clerk ,cleaner, sales personnel and etc. Hence for maximizing the difference between members of entity ,we identifying their distinguishing characteristic. The process called as generalization. GANERALIZATION
  24. 24. Staff StaffNo(PK) Name Position Salary Branch BranchNo(PK) Address Street City postcode HAS 1,1 1,M Manager mgStartDate bonus SalesPersonnel salesArea carAllowance Secretary typingSpeed {D,C} Distinguishing characteristic GANERALIZATION
  25. 25. Manager Staff_no Salary mgStartDate Bonus SalesPersonnel Staff_no Salary salesArea carAllowance Branch BranchNo(PK) Address Street City postcode 1,1 1,1 manages Product Prod_no(PK) Expired_dte Prod_name 1,M 1,1 sales by Lets assume that we have this entity type. For the manager and sales personnel ,we can see that they have the same characteristics(attribute). Hence we can minimizing the differences by creating the other entity. The process called as specialization. SPECIALIZATION COMMON CHARACTERISTICS
  26. 26. Manager Staff_no Salary mgStartDate Bonus SalesPersonnel Staff_no Salary salesArea carAllowance Staff StaffNo(PK) Name Position Salary {D,C} Branch BranchNo(PK) Address Street City postcode Product Prod_no(PK) Expired_dte Prod_name manages sales by SPECIALIZATION
  27. 27. Branch BranchNo(PK) Address Street City postcode Staff StaffNo(PK) Name Position Salary has 1..1 1..* PartTimeTemporary hourlyRate FullTimePermanent salaryScale holidayAllowance Secretary typingSpeed SalesPersonnel salesArea carAllowance Manager mgStartDate bonus 1..1 1..1 manages { C} {D, C} disjointness constraint Indicate specialization/ generalization Job role subclasses Contract employment subclasses EXAMPLE
  28. 28. Business Rule
  29. 29. Step for representation  Find the entity  Primary key  Name the relationship of the connection among business entity  Know the connection between two entity (1-m, 1-1, m-n)  Find the cardinalities- restrict number of related entities in a business situation  Generalization hierarchies- classification of business entities and organizational policies.
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