The MIX Vision: the Web emerges as a distributed database with XML as its data model

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The MIX Visionthe Web emerges as a distributed
database with XML as its data model
XML query language
XML documents
XML View(s)
XML View(s)
XML View(s)
Wrappers also export 1. Schemas Metadata
(XML-Data, RDF,...) 2. Description of
supported queries...
Wrapper
Wrapper
Native XML Database
Legacy Source
Legacy Source
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Mediated XML views
MIXm Mediator
XML View(s)
XML View(s)
XML View(s)
Wrapper
Wrapper
Data Source
XML Data Source
Data Source
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The Homebuyer Scenario

• Find homes
• in the Del Mar region,
• with at least 2 beds, 2 baths, and a pool, and
• in neighborhoods where the median annual income
  is between 60K and 100K

Web Client
XMAS Query
Results (XML)

• XMAS query

MIXm Mediator

• Query GUI

Homes mediator
Data
Data
Neighborhood mediator
National test scores
Data
Schools mediator
Home info (real estate)
Community info (name, ZIP)
Crime info (ZIP, stats)
Nhood info (demographics)
Schools info (address, size)
School district info (scores,spending,ZIP)
www.realtor.com
www.sandag.cog.ca.us
www.sannet.gov
www.homeadvisor.msn.com
www.asd.com
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California Digital Library (CDL) PrototypeThe
Art Museum Image Consortium (AMICO)
Q1 Find title, type, and image ID of
paintings
BBQ Interface
Q2 Find creator and related metadata of
paintings
XMAS query
XML doc
MIXm View based on AMICO DTD
Wrapper
AMICO XML Database
AMICO XML Database
MARC Database
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MIX Components

• Wrapper toolkit
• model information in a resource using XML DTD
  (or, XML schema), including a mapping of source
  data to DTD
• provide mapping from XML query language to source
  query language / operations
• Mediator toolkit
• allows definition of views across multiple
  resources
• views are expressed in a declarative query
  language
• query engine to execute queries on views

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MIX components...

• XML Matching And Structuring (XMAS) query
  language
• operates on a given set of XML documents to
  produce a new XML documents, using XMAS algebra
• DOM-VXD DOM Virtual XML Document extension
• a lazy implementation of DOM. Supports
  browsing/ navigation of XML documents with a
  server-side, compute as you go model

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MIX components...

• Blended Browsing and Querying (BBQ) interface
• supports navigation and querying of XML documents
• generates XMAS queries on mediator views
• generates XMAS queries modified by DOM-VXD
  operations to incrementally evaluate the result
  set, to support navigation of XML documents

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The MIX Project Team

• UCSD CSE
• Prof. Yannis Papakonstantinou
• Prof. Victor Vianu
• Pavel Velikhov
• Vincent Chu

• SDSC DICE
• Chaitan Baru
• Amarnath Gupta
• Bertram Ludaescher
• Richard Marciano

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MIX System Overview
Blended Browsing Querying (BBQ) GUI
Application
XMAS query
XML document
DOM for Virtual XML Docs
Integrated View DTD
View Definition in XMAS
MIX Mediator
DTD Inference
Query Processor
Source DTDs
RDB Wrapper
HTML Wrapper
GIS Wrapper
RDB
Arc/View
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