The last decade has seen an increase in the number of available corpus query systems. These systems generally implement a query language as well as a database model. We report on one such corpus query system, and evaluate its query language against a range of queries and criteria quoted from the literature. We show some important principles of the design of the query language, and argue for the...

Language modelling is new form of information retrieval that is rapidly becoming the preferred choice over probabilistic and vector space models, due to the intuitiveness of the model formulation and its effectiveness. The language model assumes that all terms are independent, therefore the majority of the documents returned to the ser will be those that contain the query terms. By making this ...

Several approaches for storing ontologies and their instances in databases have been proposed. As a consequence, the need of defining languages to query such ontology based databases (OBDB) appeared. In this paper, we present OntoQL, an ontology query language designed for OBDB databases. This paper particulary emphasizes on the language constructs. Several query examples showing the interest o...

In this paper we present the organization of a predicate-based query cache suitable for integration with agent-based heterogeneous database systems. The cache is managed using a tractable (sound and complete) query containment algorithm, yet there are no language restrictions placed on the applications. This is accomplished by introducing query approximation. Query approximation is a compilatio...

Both the notion of Property Graphs (PG) and the Resource Description Framework (RDF) are commonly used models for representing graph-shaped data. While there exist some systemspecific solutions to convert data from one model to the other, these solutions are not entirely compatible with one another and none of them appears to be based on a formal foundation. In fact, for the PG model, there doe...

Complex Event Processing (CEP) has been established as a well-suited software technology for processing high-frequent data streams. However, intelligent stream based systems must integrate stream data with semantical background knowledge. In this work, we investigate different approaches on integrating stream data and semantic domain knowledge. In particular, we discuss from a software engineer...

The popularity of XML as a data representation format has led to signi cant interest in querying XML documents. Although a \universal" query language is still being designed, two language proposals, XQL and XML-QL, are being implemented and applied. Experience with these early implementations and applications has been instructive in determining the requirements of an XML query language. In this...

We describe the design, functionality, and implementation of a data ow query language (DFQL), that graphically represents a query as a directed acyclic data ow graph. The language is well suited for application domains such as scientiic databases, where data analysis and visualization need to be tightly coupled with data retrieval, and the relationships between the entities are ill-deened. Bein...