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Data Management Issues in Electronic Commerce
M. Tamer ÖzsuDepartment of Computing Science
University of Alberta
What are the issues?
• Catalog development
• Intelligent querying
• Workflow management
• EC transaction atomicity
• Management of distribution and heterogeneity
Smart and Virtual Catalogs• Smart Catalog
– Searchable, annotated combinations of machine-readable (i.e., minimally processable) and machine-sensible (i.e., actually understood by computer) product data
• Virtual Catalog– Systems that dynamically retrieve information from multiple
smart catalogs and present these product data in a unified manner with their own look and feel, not that of the smart catalog
A. Keller, “Smart Catalogs and Virtual Catalogs”, In Readings in Electronic Commerce, R. Kakakota and A.B. Whinston (eds.), 1997, pp. 259-274.
Issues and Challenges
• Fully multimedia catalogs– Existing catalogs are mostly text-based virtual
catalogs with embedded images– Add more support for modeling images for
similarity searches– Add audio and video to provide product
demonstrations, voice-overs and even commercials– Structured document databases (SGML,XML) +
image databases + continuous media systems
Issues and Challenges
• More open virtual catalog environment – Single-vendor or proprietary virtual catalogs– “open” to more flexible integration of various
vendor catalogs
• Distribution– move to the Internet environment scalability
• provide search capabilities– Browsing-based access; limited search
EC Transactions
• Electronic commerce consists of processes which can be modeled as workflows.
• Workflow: “A collection of tasks organized to accomplish some business process.”
[D. Georgakopoulos]
Workflow Types• Human-oriented workflows
• Involve humans in performing the tasks.• System support for collaboration and coordination; but no system-
wide consistency definition
• System-oriented workflows• Computation-intensive & specialized tasks that can be executed by a
computer• System support for concurrency control and recovery, automatic task
execution, notification, etc.
• Transactional workflows• In between the previous two; may involve humans, require access to
heterogeneous, autonomous and/or distributed systems, ACID properties
Workflow Example
T1: Search vendor catalog T4: Send shipping instructionsT2:Place the order T5: Pay invoiceT3:Receive proforma invoice T6: Receive goods
T1 T2
T3
T4
T5
VendorCatalog
OrderDatabase
AccountsDatabase
T6
EC Transaction Atomicity
• “EC transaction” has a slightly different meaning– refers to the actual transaction of exchanging
goods for money
• Atomicity of this type of transaction is important
Atomicity Types
• Money atomicity– transfer of funds from one party to another without the
possibility of the creation or destruction of money
– Cash transaction
• Goods atomicity– Money atomicity + exact transfer of goods for money
– COD transactions
• Certified delivery– Goods atomicity + both the merchant and the customer can
prove exactly what goods were delivered
NetBill
Customer Merchant
NetBill Server
(1) Payment order
(2)PO+
invoice
(3)Approval
(4) Delivery of goods
Intelligent Querying
• Passive queries– “Find me all Montblanc fountain pens whose
price is < $500.”
• Active queries– “Whenever a Montblanc fountain pen of 1920’s
vintage becomes available for under $1000, let me know.”
– Agent technology
Issues
• Distribution
• Heterogeneity
• Autonomy
• Openness to Internet