Search results for "query language"
showing 10 items of 39 documents
User experience-based information retrieval from semistar data ontologies
2019
The time necessary for the doubling of medical knowledge is rapidly decreasing. In such circumstances, it is of utmost importance for the information retrieval process to be rapid, convenient and straightforward. However, it often lacks at least one of these properties. Several obstacles prohibit domain experts extracting knowledge from their databases without involving the third party in the form of IT professionals. The main limitation is usually the complexity of querying languages and tools. This paper proposes the approach of using a keywords-containing natural language for querying the database and exploiting the system that could automatically translate such queries to already existi…
Extending SPARQL with Temporal Logic
2009
The data integration and sharing activities carried on in the framework of the Semantic Web lead to large knowledge bases that must be queried, analyzed, and exploited efficiently. Many of the knowledge representation languages of the Semantic Web, starting with RDF, are based on directed, labeled graphs, which can be also manipulated using graph algorithms and tools coming from other domains. In this paper, we propose an analysis approach of RDF graphs by reusing the verification technology developed for concurrent systems. To this purpose, we define a translation from the SPARQL query language into XTL, a general-purpose graph manipulation language implemented in the CADP verification too…
A query language for medical statistical analysis
1991
While standard query languages support primarily the definition of single queries, in the evaluation of medical studies one usually formulates large sets of interdependent queries. A set of this type is called an integrated transaction. Our system for the definition of integrated transactions is based on the observation that in medicine a large number of statistical evaluations is founded on a conceptional model that can be structured as a tree. We describe a screen oriented tree editor for the relational data base system DBase and report on our experience with its application in the evaluation of the success rate of PTCA interventions.
On the Power of Tree-Walking Automata
2000
Tree-walking automata (TWAs) recently received new attention in the fields of formal languages and databases. Towards a better understanding of their expressiveness, we characterize them in terms of transitive closure logic formulas in normal form. It is conjectured by Engelfriet and Hoogeboom that TWAs cannot define all regular tree languages, or equivalently, all of monadic second-order logic. We prove this conjecture for a restricted, but powerful, class of TWAs. In particular, we show that 1-bounded TWAs, that is TWAs that are only allowed to traverse every edge of the input tree at most once in every direction, cannot define all regular languages. We then extend this result to a class …
The visual query language CQL for transitive and relational computation
2000
Abstract Classification query language (CQL) is a high-level visual query language with a great expressive power. In CQL the processing of ordinary relations and classifications based on transitive relationships is integrated seamlessly. Relations and classifications are represented in the visual interface in a uniform way through relation and classification skeletons. All query formulation in CQL is QBE-like – based on the intuitive way of filling constants and sample values into the skeletons. In order to guarantee great expressive power, relational and classification expressions can be nested freely with each other at unlimited nesting levels. Recursive definition of transitive processin…
Towards Graphical Query Notation for Semantic Databases
2015
We describe a notation and a tool for schema-enabled visual/diagrammatic creation of SPARQL queries over RDF databases. The notation and the tool support both the standard basic query pattern comprising a main query class and possibly linked condition classes and means for aggregate query definition and placing conditions over aggregates including also aggregation of aggregate results. We discuss the applicability of the tool for ad-hoc query formulation in practical use cases.
Temporal Logic To Query Semantic Graphs Using The Model Checking Method
2012
International audience; Semantic interoperability problems have found their solutions due to the use of languages and techniques from the Semantic Web. The proliferations of ontologies and meta-information have improved the understanding of information and the relevance of search engine responses. However, the construction of semantic graphs is a source of numerous errors of interpretation or modeling, and scalability remains a major problem. The processing of large semantic graphs is a limit to the use of semantics in current information systems. The work presented in this paper is part of a new research at the border of two areas: the semantic web and the model checking. This line of rese…
Error messages in relational database management systems: A comparison of effectiveness, usefulness, and user confidence
2021
Abstract The database and the database management system (DBMS) are two of the main components of any information system. Structured Query Language (SQL) is the most popular query language for retrieving data from the database, as well as for many other data management tasks. During system development and maintenance, software developers use a considerable amount of time to interpret compiler error messages. The quality of these error messages has been demonstrated to affect software development effectiveness, and correctly formulating queries and fixing them when needed is an important task for many software developers. In this study, we set out to investigate how participants ( N = 152 ) …
Patient documentation for the ultrasound laboratory
1991
The development of a PC based system for the storage of patient data in the echocardiography laboratory is described. Special design objectives were low cost and user friendliness, including an integrated special query language. After 3 years of use, the system stores 80000 diagnoses from 12000 patients without any relevant slowdown of response. Future developments concerning the communication between the database system and an echocardiographic sector scanner are discussed.
Publish By Example
2008
We propose an approach for producing database publishing programs by example. The main idea is to interactively build an example document, representative of the program output. The system infers from this document, without ambiguity, the publishing program. The end-user does not need to know a programming language, a query language or the database schema.