Information Organization and Databases pp 31-44 | Cite as
Entity-Oriented Queries for Semistructured Data
Abstract
In this paper, we propose an entity-oriented style of queries for semistructured data. A semistructured data represented by a large graph usually consists of subgraphs corresponding to real-world entities, in other words, subgraphs representing composite objects in object-oriented database terminology. To detect such composite objects in semistructured data, we use the exclusiveness of references. If a reference is exclusive, then we regard it as a composite link, i.e. a link connecting parts of one composite object. Then we extend usual semistructured query languages by introducing new language constructs for path expressions that match only with composite links or non-composite links. By using those constructs in combination with wild cards, we can specify queries of a form like “retrieve all entities including these data items,” which we call entity-oriented style queries. This style of query is useful especially when one does not have enough knowledge on the structure of the database.
Keywords
semistructured data query entity composite object structure discovery path expressionsPreview
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