Please use this identifier to cite or link to this item:
http://hdl.handle.net/1942/8779
Full metadata record
DC Field | Value | Language |
---|---|---|
dc.contributor.advisor | GYSSENS, Marc | - |
dc.contributor.author | VANDEURZEN, Luc | - |
dc.date.accessioned | 2008-12-03T19:16:12Z | - |
dc.date.available | 2008-12-03T19:16:12Z | - |
dc.date.issued | 1999 | - |
dc.identifier.uri | http://hdl.handle.net/1942/8779 | - |
dc.description.abstract | In this work, we concentrate on the linear constraint database model. The main contributions of this research dissertation can be summarized as follows: 1. We provide a list of queries of which we show that they can be expressed in FO + linear, i.e., the relational calculus extended with linear constraints, and a tool which can be used to prove non-expressibility of a query in FO + linear. We show that the type of the coefficients of the linear constraints used in the linear constraint database model does influence certain results. We also prove that it is undecidable whether a linear query expressible in FO + poly, i.e., the relational calculus extended with polynomial constraints, can be expressed in FO + linear. 2. We propose a technique to decompose semi-linear sets (figures representable with linear constraints) into convex cells which is expressible in FO + poly. As a side-effect, we obtain algorithms, implementable in FO + poly, to compute a finite representation of an arbitrary semi-linear set and to recompute a semilinear set from its finite representation. 3. We show that it is decidable whether a geometric figure definable with polynomial constraints is semi-linear. 4. We present two sound extensions of FO + linear for linear queries expressible in FO + poly. One extension can be seen as a bridge between GDT-based query languages and FO + linear, while the other extension results in a query language of which the expressive power can be characterized in terms of the ruler and compass constructions in the two-dimensional plane. We also show that there exist query languages which are complete for the linear queries expressible in FO + poly. | - |
dc.language.iso | en | - |
dc.publisher | UHasselt Diepenbeek | - |
dc.title | Logic-based query languages for the linear constraint database model | - |
dc.type | Theses and Dissertations | - |
local.bibliographicCitation.jcat | T1 | - |
local.type.specified | Phd thesis | - |
dc.bibliographicCitation.oldjcat | D1 | - |
item.fullcitation | VANDEURZEN, Luc (1999) Logic-based query languages for the linear constraint database model. | - |
item.contributor | VANDEURZEN, Luc | - |
item.accessRights | Open Access | - |
item.fulltext | With Fulltext | - |
Appears in Collections: | PhD theses Research publications |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
VandeurzenLuc.pdf | 976.57 kB | Adobe PDF | View/Open |
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.