DMCA
Visualization of Path Expressions in a Visual Object-Oriented Database Query Language
BibTeX
@MISC{Kim_visualizationof,
author = {Jeonghee Kim and Taisook Han and Kyu-young Whang},
title = {Visualization of Path Expressions in a Visual Object-Oriented Database Query Language},
year = {}
}
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Abstract
Although path expressions in object-oriented query languages have materialized the capability of concisely manipulating the nested structures, their presence in query expressions require complex semantic considerations. However, none of currently existing visual query languages models such complex query expressions in a concise and intuitive way partly due to either the lackofwell-defined syntax and semantics of languages or improper representation of visual constructs for path expressions. In this paper, we present visual modeling of path expressions in a visual object-oriented database query language called Visual Object Query Language (VOQL) and proper modeling of the key features related to multi-valued path expressions. VOQL directly specifies the semantics of multi-valued path expressions by employing the visual notation capable of representing a set inclusion in addition to functional relationships. Specifically, the basic visual constructs called blobs, nested blobs, binding edges, and flattening edges are introduced. Blobs and nestedblobsare used to denote sets of objects that path expressions represent. Binding edges and flattening edges are designed to visually simulate the notion of variable binding and the notion of dot functions in path expressions. The grammar of these constructs defines the syntactic components suchasVOQL terms, VOQL formulas, and VOQL query expressions in a way as in tuple relational calculus. Their semantics are provided bysyntax directed translation to corresponding counterparts in Object-Oriented Predicate Calculus (OOPC). Also, in combination with a visual scoping box for universal quantification, the constructs allow explicit visual scoping and expressing the queries with nested quantification and recursion with...
Keyphrases
path expression visual object-oriented database query language flattening edge multi-valued path expression key feature model complex query expression visual construct voql query expression visual query object-oriented query language query expression universal quantification intuitive way object-oriented predicate calculus visual scoping box visual modeling voql formula visual notation basic visual construct variable binding set inclusion nested quantification visual object query language proper modeling explicit visual scoping nested structure syntactic component suchasvoql term dot function complex semantic consideration binding edge improper representation tuple relational calculus functional relationship lackofwell-defined syntax
