Data Integration in Web Data Extraction System

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Synonyms

Web information integration and schema matching; Web content mining; Personalized Web

Definition

Data integration in Web data extraction systems refers to the task of providing a uniform access to multiple Web data sources. The ultimate goal of Web data integration is similar to the objective of data integration in database systems. However, the main difference is that Web data sources (i.e., Websites) do not feature a structured data format which can be accessed and queried by means of a query language. In contrast, Web data extraction systems need to provide an additional layer to transform Web pages into (semi)-structured data sources. Typically, this layer provides an extraction mechanism that exploits the inherent document structure of HTML pages (i.e., the document object model), the content of the document (i.e., text), visual cues (i.e., formatting and layout), and the inter document structure (i.e., hyperlinks) to extract data instances from the given W ...