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For a given document, there may be no decomposition, one level of decomposition, or multiple levels of decomposition.. And final-ly a SpecificDoc can be the basis for generating Convert

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DocumentComposition enables a document to combine lesser documents For example,

a product specification sheet may consist of various paragraphs, pictures, and tables For a given document, there may be no decomposition, one level of decomposition, or multiple

levels of decomposition DocumentComposition is a directed acyclic graph as some docu-ments are reusable in multiple contexts Note that DocumentComposition avoids symmetry (see Chapter 8) with the distinction between parent and child.

There is also DocumentFlow A Document starts out as a concept (ConceptualDoc) and

is then expressed in one or more languages (LanguageDoc) For example, a product specifi-cation sheet may have English, German, and Japanese translations LanguageDocs can be parameterized; a SpecificDoc assigns a value to each parameter For example, a Language-Doc may have a picture of an electric motor with placeholders (parameters) for length and diameter; the SpecificDoc specifies the actual length and diameter for each motor And

final-ly a SpecificDoc can be the basis for generating ConvertedDocs in formats such as PDF,

Figure 10.14 Archetype Customer: IDEF1X model

tangibleActorID

TangibleActor

.

customerID

Customer

salesData creditInformation discountSchedules tangibleActorID (FK) (AK1.1)

DocumentFlow

Figure 10.15 Archetype Document: UML model A Document is a physical

or electronic representation of a body of information

Document

name creationDate size

comment

ConceptualDoc LanguageDoc SpecificDoc ConvertedDoc

DocumentComposition

*

*

*

0 1

parent

child parent

child

parameterValue parameter *

1

*

*

format language

Attribute

name {unique}

Value

value

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130 Chapter 10 / Archetypes

HTML, and XML The model permits meaningless sequences, but this explanation describes the intended flow and application code must enforce a proper sequence

Thus there is a flow to the progression of documents Documents start out as concepts, are expressed in various languages, have parameters added, and then are converted into the desired formats

10.9 Event

An Event is an occurrence at some point in time (Figure 10.17, Figure 10.18) The notion of

an event often appears in application models An EventType is a general category of Events.

This archetype involves data and metadata and uses the shading convention from Chapter 5

EventTypes can be organized into a generalization hierarchy For example, a superevent

could be pressing a key on a keyboard A subevent would be pressing an alphanumeric key

and a further subevent would be pressing the letter X Sometimes it is helpful to organize the

definition of events by their similarities and differences using generalization

There is also a simple model of cause and effect A group of causes might lead to a group

of effects By multiple traversals of EventCausality there can be a cascade of events.

Figure 10.16 Archetype Document: IDEF1X model

documentDiscrim

documentID

Document

documentName creationDate size

comment

LanguageDoc

languageDocID (FK) language

ConceptualDoc

conceptualDocID (FK)

ConvertedDoc

convertedDocID (FK) format

SpecificDoc

specificDocID (FK)

documentDiscrim

DocComposition

parentDocID (FK) childDocID (FK)

parentDocID (FK)

attributeID

Attribute

attributeName (AK1.1)

valueID

Value

value specificDocID (FK) attributeID (FK)

LangDoc_parameter

languageID (FK) parameterID (FK)

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10.10 Flight

A Flight is the travel by an airplane between airports (Figure 10.19, Figure 10.20). The Flight

archetype is representative of many transportation routing problems A published flight is the

planned travel and an actual flight is the realized travel The frequency indicates the days of the week for a PublishedFlight The effectiveDate and expirationDate bracket the time

peri-od for which the PublishedFlight is in effect A PublishedFlightLeg refers to the scheduled

travel between airports with one takeoff and landing (A through flight has multiple legs.)

In contrast, an ActualFlightLeg refers to the actual travel made by an aircraft on a

par-ticular date The actual origin, destination, departure time, and duration can vary because of

weather and equipment problems Normally there is one ActualFlightLeg for a Published-FlightLeg and departureDate, but flight problems can lead to multiple ActualPublished-FlightLegs Each AircraftModel has a manufacturer and model number Each individual Aircraft has

a tail number and refers to an AircraftModel Note that PublishedFlightLeg to ActualFlight-Leg and AircraftModel to Aircraft illustrate the Item Description template (see Chapter 5)

Figure 10.17 Archetype Event: UML model An Event is an occurrence

at some point in time

Event

datetime

*

1

EventCausality

cause * * effect

*

*

0 1 0 1 1

*

subevent superevent

EventGeneralization

EventType

name {unique}

Figure 10.18 Archetype Event: IDEF1X model

eventGeneralizationID

EventGeneralization

superEventTypeID (FK) (AK1.1)

eventCausalityID

EventCausality

eventID

Event

datetime eventTypeID

EventCausality_cause

eventCausalityID (FK) causeEventID (FK)

EventCausality_effect

eventCausalityID (FK) effectEventID (FK) eventTypeID

EventType

eventTypeName (AK1.1)

eventGeneralizationID (FK)

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132 Chapter 10 / Archetypes

Figure 10.19 Archetype Flight: UML model A Flight is the travel by

an airline between airports

modelNumber {unique} manufacturer

AircraftModel

PublishedFlight

frequency effectiveDate

airlineCode {unique}

airlineName

Airline

0 1 1 expirationDate flightNumber

PublishedFlightLeg

scheduledDepartureTime scheduledDuration

ActualFlightLeg

actualDepartureTime actualDuration

1 {ordered}

*

departureDate 0 1

*

*

1 1 scheduledOrigin

scheduledDest

tailNumber {unique}

Aircraft

actualOrigin 1 1 actualDestination

*

*

1

*

1

*

iataCode {unique}

airportName

Airport

* {ordered}

Figure 10.20 Archetype Flight: IDEF1X model

publishedFlightID

PublishedFlight

frequency effectiveDate expirationDate aircraftModelID (FK) airlineID (FK) (AK1.1) flightNumber (AK1.2)

publishedFlightLegID

PublishedFlightLeg

scheduledDepartureTime

scheduledDuration

publishedFlightID (FK) (AK1.1)

sequenceNumber (AK1.2)

scheduledOrigin (FK)

scheduledDestination (FK)

actualFlightLegID

ActualFlightLeg

actualDepartureTime actualDuration publishedFlightLegID (FK) (AK1.1) departureDate (AK1.2)

sequenceNumber (AK1.3)

airlineID

Airline

airlineCode (AK1.1)

airlineName

aircraftModelID

AircraftModel

modelNumber (AK1.1) manufacturer

aircraftID

Aircraft

tailNumber (AK1.1) aircraftModelID (FK)

airportID

Airport

iataCode (AK1.1) airportName

actualOrigin (FK) actualDestination (FK) aircraftID (FK)

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10.11 Item

An Item is a part or a service (Figure 10.21, Figure 10.22). A RenderedService is a group of tasks that are performed In Section 10.14 many PhysicalParts can correspond to a Catalog-Part Similarly many RenderedServices can correspond to an OfferedService.

An example of an OfferedService is a business audit Corresponding RenderedServices

would be business audits performed on particular dates

A physical item can break down into lesser physical items, leading to a decomposition

tree The parent–child relationship on PhysicalItem is redundant with the Contains relation-ship of PhysicalPart (Section 10.14) If PhysicalItem and PhysicalPart are in the same

mod-el, you should omit the Contains relationship on PhysicalPart The PhysicalItem decomposition is broader in scope and subsumes PhysicalPart decomposition Section 10.14 shows relationships for CatalogPart and PhysicalPart.

RenderedService

Figure 10.21 Archetype Item: UML model An Item is a part or a service.

PhysicalItem parent

child* 0 1 quantity

startDatetime

PhysicalPart OfferedService

name

CatalogPart

CatalogItem

Figure 10.22 Archetype Item: IDEF1X model

catalogItemDiscrim

catalogItemID

CatalogItem

catalogItemDiscrim

OfferedService

offeredServiceID (FK)

offeredServiceName

CatalogPart

catalogPartID (FK)

physicalItemDiscrim

physicalItemID

PhysicalItem

physicalItemDiscrim

RenderedService

renderedServiceID (FK) startDatetime

PhysicalPart

physicalPartID (FK)

endDatetime offeredServiceID (FK)

parPhyItem_childPhyItem

childPhyItemID (FK) quantity

parentPhyItemID (FK)

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