A Query Language for Data Access in Ubiquitous Environments

Recent progress in ubiquitous computing technology is allowing development of new and so- phisticated applications that are now able to store very large data on the mobile device itself, besides access data stored remotely. Thus emerges the need to query and maintain data from portable equipments. However, traditional query languages such as SQL (Structure Query Lan- guage) and QbE (Query by Example) are inadequate for devices with small screens. Hence, this work presents QbZ (Query by Zoom), a query language based on Semantic Zoom for small-screen devices. The proposed mechanism is particularly suitable to locate and access data stored in portable equipments. In order to demonstrate the benefits of using QbZ, usability tests were conducted, as well as a comparative analysis with the existing solutions.