We introduce parameterized pattern queries as a new paradigm to extend traditional pattern expressions over sequence databases. A parameterized pattern is essentially a string mad...
We give a complexity theoretic classification of homomorphism problems for graphs and, more generally, relational structures obtained by restricting the left hand side structure ...
Query processing is one of the most, critical issues in Object-Oriented DBMSs. Extensible opt,imizers with efficient, search strategies require a cost model to select the most eff...
Georges Gardarin, Jean-Robert Gruser, Zhao-Hui Tan...
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 t...