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ACTA
2002

Adding a path connectedness operator to FO+poly (linear)

13 years 3 months ago
Adding a path connectedness operator to FO+poly (linear)
In the constraint database community, FO+poly and FO+linear have been proposed as foundations for spatial database query languages. One of the strengths of this approach is that these languages are a clean and natural generalization of Codd's relational model to a spatial setting. As a result, rigorous mathematical study of their expressiveness and complexity can be carried out. Along this line, important geometric queries involving connectivity have been shown to be inexpressible in FO+poly and FO+linear. To address this problem, we extend both languages with a parameterized path-connectivity predicate, Pconn. We show that: FO + linear + Pconn and FO+poly+Pconn,3D are closed and have PTIME data complexity. We also examine the expressiveness of FO+poly+Pconn and FO+linear+Pconn and show that parity and transitive closure are expressible in each.
Chris Giannella, Dirk Van Gucht
Added 16 Dec 2010
Updated 16 Dec 2010
Type Journal
Year 2002
Where ACTA
Authors Chris Giannella, Dirk Van Gucht
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