[Qgis-user] Model for Temporal Measurement (vector) Datasets ?

[Richard Duivenvoorde]

Hi All,

Anybody is aware of a model in which data owns a location, but THAT location has a (growing) set of [timestamp, value] observation data to it....

In GIS/QGIS everything is tabular (talking about vector here, I know meshes can have more shapes).

But in the IOT world the 'location' is 'just an attribute', and the 'other' data is actually more of interest (and growing in time).

Currently to view measurements, 'we' often replicate the location for every value/measurement: we create a 'Feature' for every time step (eg for example via a WFS)

The OGC has a SensorThingsApi (STA) standard, in which for given location you can request all values/observations (of filter a certain sensortype/parameter). So one geometry has a full table of data to it.

BUT to 'work' with that data in QGIS, you always have to 'flatten' it, one way or another, (I think), for every time step: create a feature with: location, time, value...

My Question:

- isn't there some model (or can we come up with one) in which a location can actually have a range of time/value data (like some table join like), and when you use the Temporal Controller, you style your layer by RE-using the one location, but getting the value for current Timestamp (in the TimeController). Some sort of indirect filtering....?

- or is this the mesh model (I know netcdf's in which you have often predefined meshes/location and the data/time vector is growing)?
And would a solution be to have some kind of in memory vector -> mesh loader or so???

I hope this makes sense to others. Any input appreciated.

Regards,

Richard Duivenvoorde

PS, if you want to play with SensorThingsApi:
- install: https://github.com/AirBreak-UIA/SensorThingsAPI_QGIS-plugin
- connect it to: https://airquality-frost.k8s.ilt-dmz.iosb.fraunhofer.de/v1.1/Locations
(around 5000 location and 500-million 'observations')
- load all locations in one layer, and click on a location
My point: the data is then viewable/selectable by table and graph, but NOT loadable in a sense way (yet) in QGIS...