Abstract
The problem of selecting nodes in unranked trees is the most basic querying problem for XML. We propose stepwise tree automata for querying unranked trees. Stepwise tree automata can express the same monadic queries as monadic Datalog and monadic second-order logic. We prove this result by reduction to the ranked case, via a new systematic correspondence that relates unranked and ranked queries.
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Carme, J., Niehren, J., Tommasi, M. (2004). Querying Unranked Trees with Stepwise Tree Automata. In: van Oostrom, V. (eds) Rewriting Techniques and Applications. RTA 2004. Lecture Notes in Computer Science, vol 3091. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-25979-4_8
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DOI: https://doi.org/10.1007/978-3-540-25979-4_8
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-22153-1
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