Abstract. In this paper we present a new approach for studying aggregations in the context of database query languages. Starting from a broad de nition of aggregate function, we ad...
Abstract. Controlled languages (CLs) are ambiguity-free subsets of natural languages such as English offering a good trade-off between the formal rigor of ontology and query langua...
We address aggregate queries over GIS data and moving object data, where non-spatial information is stored in a data warehouse. We propose a formal data model and query language t...
We examine the power of incremental evaluation systems that use an SQL-like language for maintaining recursively-de ned views. We show that recursive queries such as transitive clo...