Semistructured data and XML

Executive Summary

One of the most exciting developments in database research has been the convergence of ideas from the document and database communities. In order to represent data with loosely defined or irregular structure, the semistructured data model has emerged as a dynamically typed data model that allows a "schema-less" description format in which the data is less constrained than is usual in database work. At the same time the document community has developed XML as a format in which more structure is added to documents in order to simplify and standardize the transmission of data via documents. It turns out that these two representations are essentially identical!

The Penn database group has had a long-standing involvement in semistructured data, especially in the development of query languages, structure description, constraints, and type systems. It has also been part of the development of the XML-QL proposal and has worked on other aspects of XML.

Project Members

Publications

• Optimization Properties for Classes of Conjunctive Regular Path Queries [.pdf] 
  International Workshop on Database Programming Languages (DBPL) (2001)
  Alin Deutsch   Val Tannen   
  

• Publishing Relational Data in XML: the SilkRoute Approach
  IEEE Data Engineering Bulletin 24(2) (2001)
  Mary Fernandez   Atsuyuki Morishima   Dan Suciu   Wang-Chiew Tan   
  

• SilkRoute: Trading between Relations and XML [.ps] [.html] 
  International World Wide Web Conference (WWW) (2000)
  Mary Fernandez   Wang-Chiew Tan   Dan Suciu   
  

• Looking at the Web through XML glasses [.ps] [.pdf] [slides/pdf] [slides/ppt] 
  CoopIs'99 (1999)
  Arnaud Sahuguet   Fabien Azavant   
  

• Web Ecology: Recycling HTML pages as XML documents using W4F [.ps] [.pdf] 
  International Workshop on the Web and Databases (WebDB) (1999)
  Arnaud Sahuguet   Fabien Azavant   
  

• Horizontal Query Optimization on Ordered Semistructured Data [abstract] 
  International Workshop on the Web and Databases (WebDB) (1999)
  Hartmut Liefke   
  

• Union Types for Semistructured Data [abstract] 
  Technical Report MS-CIS-99-09 (1999)
  Peter Buneman   Benjamin Pierce   
  

• Querying XML Data
  IEEE Data Engineering Bulletin 22(3) (1999)
  Alin Deutsch   Mary Fernandez   Daniela Florescu   Alon Levy   David Maier   Dan Suciu   
  

• A Query Language for XML
  International World Wide Web Conference (WWW) (1999)
  Alin Deutsch   Mary Fernandez   Daniela Florescu   Alon Levy   Dan Suciu   
  

• Storing semistructured data with STORED
  Proceedings of ACM SIGMOD International Conference on Management of Data (SIGMOD) (1999)
  Alin Deutsch   Mary Fernandez   Dan Suciu   
  

• Beyond XML Query Languages [.pdf] 
  Query Language Workshop (QL'98) (1998)
  Peter Buneman   Alin Deutsch   Wenfei Fan   Hartmut Liefke   Arnaud Sahuguet   Wang-Chiew Tan   
  

• XML-QL: A Query Language for XML [.html] 
  W3C Note (1998)
  Alin Deutsch   Mary Fernandez   Daniela Florescu   Alon Levy   Dan Suciu   
  

• Adding Structure to Unstructured Data [.ps] [.pdf] 
  International Conference on Database Theory (ICDT) (1997)
  Peter Buneman   Susan Davidson   Mary Fernandez   Dan Suciu   
  

• A Query Language and Optimization Techniques for Unstructured Data [abstract] [.ps] 
  Proceedings of ACM SIGMOD International Conference on Management of Data (SIGMOD) (1996)
  Peter Buneman   Susan Davidson   G. Hillebrand   D. Suciu