Publication at Faculty of Mathematics and Physics |
2008
Abstract
Presently, there is no specialized language for complex integrity constraints description in XML documents. In this paper we present a language that combines first-order logic together with XPath language to achieve needed expressive power.
Standard quantifiers of first-order logic were extended to allow us to specify (either by count or by percentage) how many elements of the selected set must hold given constraint. The proposed language can be used in conjunction with any XML schema language.
The Incox validator supports both plain-text and XML variants of constraint specification. While the first one is easily understandable for humans, the latter meets requirements of machine processing.