Unless all the functional modules have access to and use the same data in near real-time, unless all processes are fully integrated (so that, for example a mobile sales rep can see the live inventory data for order promising), and unless users can seamlessly move from one module to another, we are not talking about coherency but rather about the hodgepodge of disconnected (or very loosely connected, in the best scenario) islands of information.
abstraction of point of sales
Web Services, layers of abstraction between application components, and so on, all to contribute to seamlessly connecting people, data and processes, that is still largely the most probable case within the context of a homogenous offering from a single vendor, and only whose all applications concurrently look at the same data. Sources and Recommended Further Readings ERP: Tools, Techniques, and Applications for Integrating the Supply Chain. Second Edition ; Carol A. Ptak, CFPIM, CIRM, and Eli