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Uncover insights from historical data using complex structured queries and information extraction mechanisms. Explore inventions, inventors, and historical events through relational database management systems.
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Structured Querying of Web Text:A Technical Challenge Michael J. Cafarella, Christopher Re, Dan Suciu, Oren Etzioni, Michele Banko University of Washington Asilomar, CA January 9, 2007
Structured Queries,Unstructured Data • “Show me some people, what they invented, and the years they died” • q(?a, ?b, ?c):- invented(?a, ?b), died-in(?a, <year> ?c)
ExDB Facts RDBMS …no one could surprising. In1877, Edisoninvented thephonograph.Although he… Types …didnt surprising. In1877, Edisoninvented thephonograph.Although he… …was surprising. In1877, Edisoninvented thephonograph.Although he… Querymiddleware Web Synonyms invented(Edison ?e, ?i) 1. Run extractors 2. Populate data model 3. Queries
ExDB Facts RDBMS …no one could surprising. In1877, Edisoninvented thephonograph.Although he… Types …didnt surprising. In1877, Edisoninvented thephonograph.Although he… …was surprising. In1877, Edisoninvented thephonograph.Although he… Querymiddleware Web Synonyms invented(Edison ?e, ?i) 1. Run extractors 2. Populate data model 3. Queries
Information Extraction • Each concept has an IE mechanism
ExDB Facts RDBMS …no one could surprising. In1877, Edisoninvented thephonograph.Although he… Types …didnt surprising. In1877, Edisoninvented thephonograph.Although he… …was surprising. In1877, Edisoninvented thephonograph.Although he… Querymiddleware Web Synonyms invented(Edison ?e, ?i) 1. Run extractors 2. Populate data model 3. Queries
Populate Data Model • Use extractions to fill tables Facts We all know that Edisoninvented the light bulb. … In 1877 Edisoncreated the light bulb. It was big news when Edison invented the light bulb. He visited citiessuch asBoston and New York. Types Synonyms IDs FDs
ExDB Facts RDBMS …no one could surprising. In1877, Edisoninvented thephonograph.Although he… Types …didnt surprising. In1877, Edisoninvented thephonograph.Although he… …was surprising. In1877, Edisoninvented thephonograph.Although he… Querymiddleware Web Synonyms invented(Edison ?e, ?i) 1. Run extractors 2. Populate data model 3. Queries
Query Processing • For non-projecting queries, we can compute top-k queries • Comb. fn is product of probabilities • For projecting queries, we compute the disjunction of m probabilistic events • In general NP-hard, so we approximate using the panel of experts
Related Work • Query Systems: • CIMple (CIDR07), AVATAR (DEBul06) • Liu, Dong, Halevy (WebDB06) • Gubanov and Bernstein (WebDB06) • Extraction: Sarawagi (VLDB06 and others), Etzioni (WWW04), … • Probabilistic DBs: MYSTIQ, Trio, … • Deep web, reference reconciliation, …
Our prototype • Web crawl: 90M pages • Facts: 338M tuples, 102M objects • Types: 6.6M instances • Synonyms: 17k pairs • No IDs or FDs yet • Most queries in ~30 seconds • Built on DB2 with custom middleware; we want to try a compressed C-store