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10.17 Product 139 tended). In reality, at most one Person can hold a Position at a time and application code must enforce this constraint. The model does not require that the position structure be a hierarchy, although that is the usual case. The model instead supports matrix management (a Position may report to multi- ple parent Positions). 10.17 Product A Product is the packaging of a physical item for a particular marketplace (Figure 10.33, Figure 10.34). For example, a bank can have a checking account service and tailor the service into products for various markets. One product might be an interest-bearing checking ac- count. Another might couple a checking account with discounts for various businesses. A third product might have low fees for students. A product can consist of multiple items. Figure 10.31 Archetype Position: UML model. A Position is a job held by someone in an organization. effectiveDate expirationDate MgmtHierarchy PositionLink effectiveDate expirationDate Position title effectiveDate expirationDate Assignment effectiveDate * 11 * 0 1 Organization Person ** 1 1 parent child expirationDate 1 * 1 root {At most one Person can hold a Position at a time.} Figure 10.32 Archetype Position: IDEF1X model. positionID Position title effectiveDate expirationDate personID Person . . . assignmentID Assignment effectiveDate expirationDate positionID (FK) personID (FK) positionLinkID PositionLink effectiveDate expirationDate parentPositionID (FK) childPositionID (FK) mgmtHierarchyID MgmtHierarchy effectiveDate expirationDate rootPositionID (FK) (AK1.1) organizationID (FK) organizationID Organization . . . 140 Chapter 10 / Archetypes 10.18 Role A Role is a function played by someone or something (Figure 10.35, Figure 10.36). Each Role corresponds to one Entity and can also have a Relationship. Similarly, each RoleType corresponds to one EntityType and can also have a RelationshipType. This archetype is an excerpt from a metamodel but the notion of a role often arises for application models. Sometimes it is helpful to have explicit role tables as the Actor and Ad- dress archetypes illustrate. Note that the role archetype has two homomorphisms. • EntityType to Entity corresponds to RoleType to Role. • RelationshipType to Relationship corresponds to RoleType to Role. Figure 10.33 Archetype Product: UML model. A Product is the packaging of a physical item for a particular marketplace. * Product name * 1 marketingData PhysicalItem Vendor * Figure 10.34 Archetype Product: IDEF1X model. physicalItemID PhysicalItem . . . vendorID Vendor . . . productID Product productName marketingData vendorID (FK) PhysItem_Product physicalItemID (FK) productID (FK) Figure 10.35 Archetype Role: UML model. A Role is a function played by someone or something. Entity Relationship RoleType name Role 1 1 * * * 1 0 1 * 1 0 1 ** * 1 EntityType name RelationshipType name 10.19 Transaction 141 10.19 Transaction A Transaction is an exchange that must be completed in its entirety or not at all (Figure 10.37, Figure 10.38). There are two major usages — in finance and in computing. Figure 10.36 Archetype Role: IDEF1X model. entityTypeID EntityType entityTypeName (AK1.1) roleTypeID RoleType roleTypeName entityTypeID (FK) relationshipTypeID (FK) relationshipTypeID RelationshipType relationshipTypeName entityID Entity entityTypeID (FK) roleID Role roleTypeID (FK) entityID (FK) relationshipID (FK) relationshipID Relationship relationshipTypeID (FK) * 1 Figure 10.37 Archetype Transaction: UML model. A Transaction is an exchange that must be completed in its entirety or not at all. Transaction datetime priority TransactionType name {unique} TransactionElement name outcome * 1 Figure 10.38 Archetype Transaction: IDEF1X model. transactionID Transaction datetime priority outcome transactionTypeID (FK) transactionTypeID TransactionType transactionTypeName (AK1.1) transactionElementID TransactionElement transactionElementName transactionID (FK) 142 Chapter 10 / Archetypes A financial transaction is an exchange of assets (information, goods, services, money) between two parties. For example, a stock holding might be sold on a stock exchange. A company may split its stock awarding additional shares to the owner as well as money in lieu of partial shares. A computing transaction (often involving a database) is a group of commands that is treated as a unit of work. All commands must be completed before the transaction is success- ful. Partial work is not permitted; if the transaction cannot be completed all work is undone. Each Transaction has a TransactionType that determines the precise processing. A trans- action outcome is committed or rolled back. The TransactionElements are either the details of a financial transaction or the constituent commands for a computing transaction. 10.20 Vendor A Vendor is someone involved in the sale of products (Figure 10.39, Figure 10.40). Vendor reifies the vendor role for a TangibleActor (usually an organization, see Section 10.2). Ven- dors often have special data to collect, such as supply data, credit information, and order lead time. You could use softcoding (see Chapter 13) to capture vendor data, but an alternative is to define a distinct entity type as shown here. 10.21 Chapter Summary Archetypes are abstractions that often occur and transcend individual applications. You should keep them in mind as you construct models. Table 10.1 summarizes the archetypes. 0 1 Vendor supplyData 1 creditInformation orderLeadTime Figure 10.39 Archetype Vendor: UML model. A Vendor is someone involved in the sale of products. TangibleActor Figure 10.40 Archetype Vendor: IDEF1X model. vendorID Vendor supplyData creditInformation orderLeadTime tangibleActorID (FK) (AK1.1) tangibleActorID TangibleActor . . . 10.21 Chapter Summary 143 Archetype Definition Sample applications Related terms Account a label for recording, reporting, and manag- ing a quantity of some- thing • accounting • business • computing • financial •travel • account payable • account receivable • credit card account • email account • expense account • frequent flyer account • general ledger account Actor someone or something that is notable in terms of data or relationships widespread use across applications • customer • organization •party •person • vendor Address a means for communi- cating with an actor Asset something of value • business • financial • security Contract an agreement for the supply of products • business • financial • agreement • purchase order • sales order Course a series of lessons about a subject • education Customer someone involved in the purchase of prod- ucts CRM (customer rela- tionship management) Document a physical or elec- tronic representation of a body of information Event an occurrence at some point in time Flight the travel by an air- plane between airports • aviation • shipping •trucking •route Item a part or a service • commerce • manufacturing •part • product • service Table 10.1 Summary of Archetypes Note: Keep them in mind as you construct models. The use of an archetype can lead to a breakthrough. . the owner as well as money in lieu of partial shares. A computing transaction (often involving a database) is a group of commands that is treated as a unit of work. All commands must be completed. 10.2). Ven- dors often have special data to collect, such as supply data, credit information, and order lead time. You could use softcoding (see Chapter 13) to capture vendor data, but an alternative. terms of data or relationships widespread use across applications • customer • organization •party •person • vendor Address a means for communi- cating with an actor Asset something of value

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