Database Aspects of Location-Based Services

Adopting a data management perspective on location-based services, this chapter explores central challenges to data management posed by location-based services. Because service users typically travel in, and are constrained to, transportation infrastructures, such structures must be represented in the databases underlying high-quality services. Several integrated representations - which capture different aspects of the same infrastructure - are needed. Further, all other content that can be related to geographical space must be integrated with the infrastructure representations. The chapter describes the general concepts underlying one approach to data modeling for location-based services. The chapter also covers techniques that are needed to keep a database for location-based services up to date with the reality it models. As part of this, caching is touched upon briefly. The notion of linear referencing plays an important role in the chapter's approach to data modeling. Thus, the chapter offers an overview of linear referencing concepts and describes the support for linear referencing in Oracle.