fiware cygnus - Orion chronological consultation -


i know if possible consult older data using orion context broker.

eg: have temperature attribute , value changing (4,5,9,10,30,2). in examples , specification had impression possible consult latest value (in case 2).

is accurate? if older data deleted?

it's correct. that's way in orion works, , makes sense of use cases. orion context broker, whenever context changes (and attribute value part of context) orion returns new value.

however, if want have historical context there fiware solutions that. in particular, cygnus can used persist such historical context in several storage backends (hdfs, mysql, ckan, etc.). among these backends, short term historic particularly interesting in case, given provides ngsi-like rest api interface getting secuences of values, 1 showing.

please have documentation on these componentes further details.


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