ESSQL - Typical Application

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This is an advanced topic for implementers. It is designed to assist programmers and implementers to decide if this library is suitable for their specific application. Developers should note that, with little application programming, replacement of existent embedded systems may be easily achieved.

This application is fictional but included here to illustrate the functionality of the library. We describe a very simplified security application. This application describes an access control system where the events occuring on the "client embedded system" are mirrored to a SQL server. Bear in mind that the the application assumes that the SQL server is not making security decisions, but instead is representing, in real-time, the events which have transpired on the embedded system. Further, we shall assume that the embedded system permits emulation of devices remotely.

Refer to Figure 1 to see a basic hardware configuration. Remember this is not the only configuration possible but is useful to describe the ESSQL system hardware configuration for illustrative purposes.

Next, refer to Figure 2, a fictional system used to describe the simplified real-time security system. Pay particular attention to the TABLES and RULES definitions. As the SQL backend server is also performing updates to the "logical_device_status" the backend also logs events. This ensures rapid updates and logging and eliminates need for the embedded system to also send logging events. While this is not foreign to SQL administrators, elimination of the conversion routines in the embedded system preserves performance.

Next see how the embedded client communicates with the ES_SQL server. Refer to Client API diagram to