Towards Aggregated Answers for Semistructured Data
Semistructured data ,,,, are used to model data transferred on the Web for applications such as e-commerce , biomolecular biology , document management ,, linguistics , thesauri and ontologies . They are formalized as trees or more generally as (multi-)graphs ,. Query languages for semistructured data have been proposed ,,,, that, like SQL, can be seen as involving a number of variables , but, in contrast to SQL, give rise to arrange the variables in trees or graphs reflecting the structure of the semi- structured data to be retrieved. Leaving aside the “construct” parts of queries, answers can be formalized as mappings represented as tuples, hence called an- swer tuples, that assign database nodes to query variables. These answer tuples underly the semistructured data delivered as answers.
KeywordsQuery Language Target Candidate Evaluation Problem Conjunctive Query Query Path
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