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5.4 Data Selection
Users can enter multiple data records for the same measurement at the same location.
When this happens it may be difficult to determine which reading the user wants
reported. While all data readings taken will be logged in the database, only one reading
can be displayed for each measurement at a specific location on live displays of the data.
There are two primary intentions a user could have when entering multiple data records
for the same measurement at the same location. One scenario is the old data was incorrect
due to instrument malfunction or human error. In this case the user wants only the new
data reported. A second scenario is that the user wants to be sure he got an accurate
reading at a site and takes multiple readings, desiring to report the average of these
readings.
Because there would be a large amount of overhead associated with maintaining these
intentions for each measurement, the user must specify this while using the Configurator
tool for all readings in the entire field study. Based on this decision, the system will only
use either the most recent data or the average of all data for a location when setting up
live data displays. For all field testing of this system, only most recent data was used for
live display.
5.5 Creation of Output Table
The relational database is a robust means of collecting not only all the data, but all of the
conditions surrounding the data collection. However, the relational database is not in the
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