Queries and Constraints on Semi-Structured Data
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Queries and Constraints on Semi-structured Data
We extend the model for semi-structured data proposed in [4], where both databases and schemas are represented as graphs, with the possibility of expressing different types of constraints on the nodes of the graphs, and defining queries which are used to select graphs from a database. We show that reasoning tasks at the basis of query optimization, such as schema subsumption, query-schema compa...
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