The visual query language for an object-oriented knowledge-based system
Ming Xu, Yong-Jun Wang, Yijie Wang, Kang Zhang, Yanchun Zhang · 2003
The user interface of the object-oriented knowledge-based system CAOBS/v1.2 is a visual query subsystem consisting of a flexible visual query language (VKQL), and a knowledge base browser/editor. With the visual language, the user can express query requirements by constructing query graphs. VKQL absorbs the key features of some existing visual query languages, and adds more advanced functions. The paper presents the design and implementation of VKQL and compares VKQL with other similar query languages.