Related section
Using a readingsFilter in the related section of a $findWithRelated query#
Insert a readingsFilter in the related section of a $findWithRelated query to return the related items, such as HVAC air handling units, in a collection that have a relationship to telemetry items whose readings match your query.
Structure your $findWithRelated query as follows:
{ "$findWithRelated": { "parent": { "collectionDesc": { "<property to identify a collection you want to query. In this example, an asset collection>": "<identifying value>" }, "query": { //<simple query to find matching related items in the collection. //In this example we want to find HVAC air handling units> }, }, "related": [ { "relatedDesc": { "<property to identify the telemetry collection you want>": "<value>" }, "readingsFilter": { "query": { //<Valid simple telemetry reading query to filter parent //related items, in this example, HVAC air handling units> }, } "as": "sensor", } ] }}
The following code example returns a list of HVAC units whose sensors recorded a temperature above 11℃ on or after 09:00, December 1st, 2021:
Example request
{ "$findWithRelated": { "parent": { "query": { "properties.dtCategory.val": "HVAC Air Handling Unit" }, "collectionDesc": { "_userItemId": "asset_coll_jPQCU4n096" } }, "related": [ { "relatedDesc": { "_relatedUserType": "iaf_telemetry_timeseries" }, "readingsFilter": { "query": { "$and": [ { "temp": { "$gte": 10 } } ] } }, "as": "sensor" } ] }}
Example response
{ "_list": [ { "_uri": "/nameduseritems/634cd7e89d34dd31017382e0", "_name": "Building assets Collection", "_userType": "iaf_ext_asset_coll", "_tipId": "634cd7e89d34dd31017382e1", "_versions": [ { "_userItemDbId": "634cd7e89d34dd31017382e0", "_relatedItems": { "_pageSize": 3, "_list": [ { "Asset Name": "5SPD.R1.HV.AHU.0002", "sensor": { "_pageSize": 1, "_list": [ { "_sourceId": "e3e052f9-0156-11d5-9301-0000863f27ad-00000131", "_id": "634ce4999d34dd31017382ef", "_metadata": { "_updatedById": "057ce6fd-a306-4bdc-8514-0a45c453f7ec", "_createdAt": 1665983641162, "_createdById": "057ce6fd-a306-4bdc-8514-0a45c453f7ec", "_updatedAt": 1665983641162 } } ], "_offset": 0, "_total": 1 }, "_id": "634ce4769d34dd31017382ed", "_metadata": { "_updatedById": "057ce6fd-a306-4bdc-8514-0a45c453f7ec", "_createdAt": 1665983606783, "_createdById": "057ce6fd-a306-4bdc-8514-0a45c453f7ec", "_updatedAt": 1665983606783 }, "properties": { "dtCategory": { "val": "HVAC Air Handling Unit" }, "Containing Floor": { "val": 1 } } }, { "Asset Name": "5SPD.R1.HV.AHU.0003", "sensor": { "_pageSize": 1, "_list": [ { "_sourceId": "a54052f9-0156-11d5-9301-0000863f27ad-000001454", "_id": "634ce4999d34dd31017382f0", "_metadata": { "_updatedById": "057ce6fd-a306-4bdc-8514-0a45c453f7ec", "_createdAt": 1665983641163, "_createdById": "057ce6fd-a306-4bdc-8514-0a45c453f7ec", "_updatedAt": 1665983641163 } } ], "_offset": 0, "_total": 1 }, "_id": "634ce4769d34dd31017382ee", "_metadata": { "_updatedById": "057ce6fd-a306-4bdc-8514-0a45c453f7ec", "_createdAt": 1665983606783, "_createdById": "057ce6fd-a306-4bdc-8514-0a45c453f7ec", "_updatedAt": 1665983606783 }, "properties": { "dtCategory": { "val": "HVAC Air Handling Unit" }, "Containing Floor": { "val": 2 } } }, { "Asset Name": "5SPD.R1.HV.AHU.0004", "sensor": { "_pageSize": 0, "_list": [], "_offset": 0, "_total": 0 }, "_id": "634ce6ac9d34dd31017382f7", "_metadata": { "_updatedById": "057ce6fd-a306-4bdc-8514-0a45c453f7ec", "_createdAt": 1665984172343, "_createdById": "057ce6fd-a306-4bdc-8514-0a45c453f7ec", "_updatedAt": 1665984172343 }, "properties": { "dtCategory": { "val": "HVAC Air Handling Unit" }, "Containing Floor": { "val": 3 } } } ], "_offset": 0, "_total": 3 }, "_id": "634cd7e89d34dd31017382e1", "_isTip": true, "_metadata": { "_updatedById": "057ce6fd-a306-4bdc-8514-0a45c453f7ec", "_createdAt": 1665980392076, "_createdById": "057ce6fd-a306-4bdc-8514-0a45c453f7ec", "_updatedAt": 1665980392076 }, "_version": 1 } ], "_irn": "itemsvc:nameduseritem:634cd7e89d34dd31017382e0", "_namespaces": [ "Lnt_GglJp74V" ], "_nextVersion": 2, "_shortName": "asset_coll", "_tipVersion": 1, "_versionsCount": 1, "_itemClass": "NamedUserCollection", "_userItemId": "asset_coll_jPQCU4n096", "_id": "634cd7e89d34dd31017382e0", "_metadata": { "_updatedById": "057ce6fd-a306-4bdc-8514-0a45c453f7ec", "_createdAt": 1665980392072, "_createdById": "057ce6fd-a306-4bdc-8514-0a45c453f7ec", "_updatedAt": 1665980392072 }, "_kind": "collection" } ], "_time": "62ms"}