Measurand<\/em> – a measurand is a physical quantity to be measured e.g. Temperature, Relative Humidity, etc. Sensors are associated with a Measurand.<\/p>\n Sensor<\/em> holds the key data for each sensor. There is no Sensor Type, but the SensorFunction column effectively has a pointer to the code which handles the reading.<\/p>\n The Actuator<\/em> table keeps track of the hub outputs such as fan relays, indicators, etc.<\/p>\n Sample<\/em> is where current values are logged, which becomes the source for graphs on the website.<\/p>\n The EventQueue<\/em> is important, because it queues events such as a threshold being reached or an impulse from the occupant, until they can be processed by the Rules Engine.<\/p>\n In the next post we will test that our controller can access the database.<\/p>\n","protected":false},"excerpt":{"rendered":" It’s worth stepping back at this point to take a look at the database schema, and highlight some of the key tables. Zone – a zone is a physical sub-space within the area being monitored. Typically a room: Kitchen, Bathroom, etc. but can represent larger spaces such as Outside or Locality. Zones have x, y, … <\/p>\n![\"\"](\"https:\/\/test.warrensoft.co.uk\/wp-test\/wp-content\/uploads\/2017\/03\/DatabaseBlockDiagram-300x158.png\")
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