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We then analyze the expressive power of several real query languages, including languages based on the relational calculus, languages with set operators and aggregate functions, and procedural query languages ... Fhst, we provide a definition of relational query languages and their expressive power. ... Query languages and expressive power We adopt the formal definitions of relational database, query, and query language essentially as stated in [Cl+] . ...doi:10.1145/582153.582190 dblp:conf/popl/Cooper82 fatcat:onftmtsrpfgl3l6has3n7ieibm
International Journal on Cybernetics & Informatics
For instance, querying a system with medical and hospital data can be used to address the problem of location wise medical decision making. ... Solutions to many real time scenarios can be easily provided when there is powerful graph databases like neo4j that can be used to efficiently query the graphs with multiple attributes. ... Because Neo4j is a graph database with powerful and simple query language (Cypher Query Language-CQL) capable of expressing complex queries. ...doi:10.5121/ijci.2016.5224 fatcat:hrrsog5lencjfnq4bbrma5ck2m
In this paper, we present a novel query language called SVQL for video databases, which is developed based on an extension of the traditional database query language SQL. ... , making SVQL with powerful expressiveness. ... temporal relationships of objects Support for queries based on spatial directional relationships of objects Support for queries based on spatial topological relationships of objects Support for queries ...doi:10.14257/ijdta.2015.8.3.20 fatcat:ubptornlfrfyfei7cgwxbbmrby
A fuzzy calculus query language is constructed based on the relational calculus and a fuzzy algebra query language is also constructed based on the relational algebra. ... In addition, this paper proves a fuzzy relational completeness theorem such that both the languages have equivalent expressive power to each other. ... RELATIONAL COMPLETENESS THEOREM FOR FUZZY DATABASE QUERY LANGUAGES The relational database theory establishes the relational completeness theorem such that the relational calculus is equivalent in expressive ...doi:10.1109/69.204096 fatcat:ymk7eyqfrrasvddy7jiwoctyba
For instance, querying a system with medical and hospital data can be used to address the problem of location wise medical decision making. ... Solutions to many real time scenarios can be easily provided when there is powerful graph databases like neo4j that can be used to efficiently query the graphs with multiple attributes. ... Because Neo4j is a graph database with powerful and simple query language (Cypher Query Language-CQL) capable of expressing complex queries. ...doi:10.5121/acij.2016.7303 fatcat:ystap2hk4vbjrhye2zulxehyci
We illustrate this with a case, investigating possible revisions of the relational algebra in order to overcome weaknesses of the division operator in connection with universal queries. ... Theories distinguishing between -genuine differences- in language has been called for, and we propose that such differences can be observed through a notion of expressive mode. ... Relational Comparison and Relational Algebra In connection with database query-languages the term relational comparison refers to predicates, for use in selectionconditions, where one or more of the arguments ...doi:10.5281/zenodo.1056289 fatcat:7ddmm5uygvarhd6jo7r2bg3xtu
Part of the results in this paper appeared under the title"On the power of stratified logic programs with value invention for expressing database transformations" in International Conference on Database ... The language ILOG c , originally proposed to express queries in the context of object databases, can be syntactically limited to specify relational queries only, that is, generic database mappings. ... In this paper we study the expressive power of a family of query languages with value invention in the context of relational databases. ...doi:10.1006/inco.1998.2734 fatcat:cjhwwnxtuba55jz5ausf3vknji
We give a formal definition of this language and illustrate it by examples. We then proceed to surveying the current state of knowledge regarding the expressive power and complexity of this core. ... This article proposes a core query algebra for probabilistic databases. ... The right degree of expressive power. The language should be powerful enough to support important queries. ...doi:10.1145/1519103.1519116 fatcat:ex2el4xphvdzdo6hjxvqgmgnne
Functional Models of Cognition
database languages, and the balance between expressive power and complexity for such systems is analyzed in greater detail. ... An "optimal" balance between expressive power and complexity is the key that explains the success of some formal systems and languages that are widely used in computer science and applications. ... The expressiveness of a query language is related to the class of queries that the language can express. ...doi:10.1007/978-94-015-9620-6_7 fatcat:s66seglujrf4bohfdd6ul2ibsy
Lecture Notes in Computer Science
This paper investigates the possibility of exploiting formal analysis tools developed in the database eld for the purpose of studying the expressive power of description logics augmented with rule-based ... We report a preliminary analysis on the expressive power of such hybrid languages. Two speci c languages coupling a terminological component with Horn rules are considered. ... In the context of databases, expressive power of query languages has been measured in at least three di erent ways: 1. With respect to a speci c property, such as transitive closure. ...doi:10.1007/3-540-64823-2_16 fatcat:52exjirv4fevzjajms6jivmghy
In the standard relational model for databases, one models data tables as first-order relations, and expresses data manipulations (in particular, database queries) in the relational algebra (an op- erational ... algebra was accordingly extended with two opera- tors (nesting and unnesting) to a basic query language for nested relational databases. ...
They examine the expressive power of various restrictions and extensions of this language and compare it with various extensions of the nested relational algebra. ... Examples of queries inexpressible in these languages are the parity test, transitive closure of a binary relation, and the test for balanced binary trees. ...
Lecture Notes in Computer Science
We address in this paper the issue of designing a simple, user friendly query language for string databases. ... We focus on the language F O( ), which is classical rst order logic extended with a concatenation operator, and where quanti ers range over the set of all strings. ... The authors whish to thanks Luc Segou n for fruitful discussions on the subject, and Leonid Libkin and Victor Vianu for comments on an earlier version of this paper. ...doi:10.1007/3-540-44543-9_5 fatcat:p7mbmnb4mnccddtkdy7kk2gbaa
XML management systems vary widely in their expressive power and query-processing efficiency, and users should choose the XMLMS that best meets their needs. ... XML queries with an expressive power similar to that of Datalog, 2 the database logic, for relational models are relational queries. ... XML Database Systems The relational database community's focus on XML as another data format for relational and object-relational data-processing tools led to the development of query languages such as ...doi:10.1109/mic.2002.1020325 fatcat:qkkntfeso5bkxa45ru6emhaasq
Our query language approach is based on the incorporation of deductive aspects to object-orientation. ... So far in the context of this paradigm a big problem has been the lack of a query language suitable to an ordinary end user. ... On the one hand this gives great expressive power for the user and on the other hand the user has to specify queries on the basis of visual constructs of a low abstraction level. ...doi:10.1016/s0950-5849(00)00118-x fatcat:5caahyvwr5hkncqiyznfic5l5i
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