Past Research Projects

	Hy+ We have implemented a second generation data visualization prototype, called Hy+, that embodies a visual query language called GraphLog. Hy+ and GraphLog support visual querying and manipulation of data that are well described by graphs, networks and hierarchical diagrams, such as occur in transportation networks, CAD/CAM, software development, and other new areas of application of database technology.
	Similarity-based Queries We have developed a general framework for expressing similarity queries and have tuned this framework to the needs of time series data domain. This is achieved by allowing transformations to be applied to Fourier series representation of a sequence. We have also developed algorithms for efficiently processing queries expressed within this framework.
	Spatial databases Spatial databases and related indexing techniques in object relation databases.
	Transaction Logic Transaction Logic was developed by Anthony J. Bonner and Michael Kifer. It is an extension of predicate logic that accounts for state changes in database, logic programs and arbitary logical theories in a clean and declarative way. Unlike many other logics, Transaction Logic allows a user to program transactions and has well-defined procedural and declarative semantics in its "Horn" version.
	WebCat WebCat is methodology for integrating large collections of HTML pages organized in some kind of hierarchy using domain ontologies. WebCat uses a standard wrapper/mediator architecture. The novelty of the method resides in the high level, declarative way in which we build our wrappers and in the integration method called Information Integration with Semantic.
	WebOQL WebOQL is a system developed at the University of Toronto for extracting data from semistructured sources. If you need to manipulate Web documents or hypertexts as if they were small databases, WebOQL may be the tool to solve your problem. Check out the live examples below to get an idea of what WebOQL can do for you.
	WebSQL WebSQL is a SQL-like query language for extracting information from the web. Its capabilities for performing navigation of web hypertexts makes it a useful tool for automating several web-related tasks that require the systematic processing of either all the links in a page, all the pages that can be reached from a given URL through paths that match a pattern, or a combination of both. WebSQL also provides transparent access to index servers that can be queried via the Common Gateway Interface.