Mobile databases or write-through Web caches

Finally, Oracle is going public with the work we have been doing on Web data, specifically in the context of mobile devices. In the past, most developers, including Oracle, have developed full-fledged relational databases for mobile devices. Our group at Oracle has took a different approach due to the uncertain outlook on connectivity and the need for responsiveness and availability over consistency.

We have developed a tiny embedded database, rather a write-through cache for mobile Web browsers that provides transparent access to Web data for read-write operations. A technical paper on our approach describes AtomDB, the motivations for it, and the future work to make AtomDB a core component of the rich, mobile-ready Web. Here's an excerpt from that paper Going far without the bars:

Mobile application developers can’t avoid human computer interface challenges, limited network connectivity, and harried users, but they shouldn't have to deal with new data storage and communication models and synchronization issues. In this paper we explore how the AJAX application model and the Atom data model, widely used for on-line applications, can be combined to create seamless on-line/off-line model for mobile applications. We show how existing applications can be made robust to intermittent connectivity and limited battery capacity without any application changes. This is achieved through a local Web data proxy and synchronization architecture called BITSY. We illustrate this approach with two robust mobile Web applications, one existing and another new, running on AtomDB, an implementation of BITSY built as a browser plug-in.