A Query Translation Scheme for Rapid Implementation of Wrappers

Wrappers provide access to heterogeneous information sources by converting application queries into source speci c queries or commands. In this paper we present a wrapper implementation toolkit that facilitates rapid development of wrappers. We focus on the query translation component of the toolkit, called the converter. The converter takes as input a Query Description and Translation Language QDTL description of the queries that can be processed by the underlying source. Based on this description the converter decides if an application query is a directly supported, i.e., it can be translated to a query of the underlying system following instructions in the QDTL description; b logically supported, i.e., logically equivalent to a directly supported query; c indirectly supported, i.e., it can be computed by applying a lter, automatically generated by the converter, to the result of a directly supported query.

• Type: Conference
• Year: 1995
• Where: DOOD
• Authors: Yannis Papakonstantinou, Ashish Gupta, Hector Garcia-Molina, Jeffrey D. Ullman
• Keywords: Database, DOOD 1995, Query Description, Query Translation Component, Wrappers Provide Access