Earliest Query Answering for Deterministic Streaming Tree Automata and a Fragment of XPath
نویسندگان
چکیده
We study the concept of earliest query answering as neededfor streaming XML processing with optimal memory man-agement. We derive lower complexity bounds showing thatearliest query answering for Forward XPath is not feasible inpolynomial time combined complexity except if P=NP. Wethen distinguish a fragment of Forward XPath with negationthat enjoys P-time earliest query answering under schemaassumptions. Our algorithm is obtained from a new earliestquery answering algorithm for deterministic streaming treeautomata (dSTAs) and a new compilation method from thefragment of Forward XPath to dSTAs, both in P-time.
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تاریخ انتشار 2008