ICDT
1999
ACM
14 years 5 months ago
1999
ACM
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...
ICDT
1999
ACM
14 years 5 months ago
1999
ACM
In data integration systems, queries posed to a mediator need to be translated into a sequence of queries to the underlying data sources. In a heterogeneous environment, with sour...
ICDT
1999
ACM
14 years 5 months ago
1999
ACM
Abstract. In this paper we consider databases representing information about moving objects (e.g. vehicles), particularly their location. We address the problems of updating and qu...
ICDT
1999
ACM
14 years 5 months ago
1999
ACM
ICDT
1999
ACM
14 years 5 months ago
1999
ACM
A large number of database index structures have been proposed over the last two decades, and little consensus has emerged regarding their relative e ectiveness. In order to empir...
ICDT
1999
ACM
14 years 5 months ago
1999
ACM
The vast number of design options in replicated databases requires efficient analytical performance evaluations so that the considerable overhead of simulations or measurements can...
ICDT
1999
ACM
14 years 5 months ago
1999
ACM
Electronic newsgroups are one of the primary means for the dissemination, exchange and sharing of information. We argue that the current newsgroup model is unsatisfactory, especial...