Azure Stream Analytics GetRecordPropertyValue puzzle - azure-stream-analytics

Question

Could anyone please spot easily what am I doing wrong here?
I'm using the query below:
SELECT
GetArrayElement(Requests.context.custom.dimensions, 0),
GetType( GetArrayElement(Requests.context.custom.dimensions, 0)),
GetRecordPropertyValue(GetArrayElement(Requests.context.custom.dimensions, 0), "Response-Body")
INTO
PowerBICreateScheduleDurations
FROM
AppInsightsIncomingRequests AS Requests
To parse this input file:
{
"request": [{
"id": "dff22190-ecc8-44d2-aa3f-453c3d533c4d",
"name": "",
"count": 1,
"responseCode": 401,
"success": false,
"url": "",
"urlData": {
"base": "",
"host": "",
"hashTag": "",
"protocol": "https"
},
"durationMetric": {
"value": 4786.0,
"count": 1.0,
"min": 4786.0,
"max": 4786.0,
"stdDev": 0.0,
"sampledValue": 4786.0
}
}
],
"internal": {
"data": {
"id": "f0b0f800-ab16-11e8-89c8-ed6412963258",
"documentVersion": "1.61"
}
},
"context": {
"data": {
"eventTime": "2018-08-28T23:05:54.8884157Z",
"isSynthetic": false,
"samplingRate": 100.0
},
"cloud": {},
"device": {
"type": "PC",
"roleName": "",
"roleInstance": "",
"screenResolution": {}
},
"session": {
"isFirst": false
},
"operation": {
"id": "dff22190-ecc8-44d2-aa3f-453c3d533c4d",
"parentId": "dff22190-ecc8-44d2-aa3f-453c3d533c4d",
"name": ""
},
"location": {
"clientip": "0.0.0.0",
"continent": "North America",
"country": "United States"
},
"custom": {
"dimensions": [{
"Response-Body": "response 0"
}, {
"Operation Name": ""
}, {
"ApimanagementRegion": ""
}, {
"ApimanagementServiceName": ""
}, {
"Cache": "None"
}, {
"API Name": ""
}, {
"HTTP Method": "GET"
}
],
"metrics": [{
"Response Size": {
"count": 1.0,
"max": 343.0,
"min": 343.0,
"sampledValue": 343.0,
"stdDev": 0.0,
"sum": 343.0,
"value": 343.0
}
}, {
"Request Size": {
"count": 1.0,
"max": 0.0,
"min": 0.0,
"sampledValue": 0.0,
"stdDev": 0.0,
"sum": 0.0,
"value": 0.0
}
}, {
"Client Time (in ms)": {
"count": 1.0,
"max": 0.0,
"min": 0.0,
"sampledValue": 0.0,
"stdDev": 0.0,
"sum": 0.0,
"value": 0.0
}
}
]
}
}
}
The desired behavior is for the GetRecordPropertyValue... line to extract the "response 0" string, yet it returns null. The downloaded output is below:
[{
"getarrayelement": {
"Response-Body": "response 0"
},
"gettype": "record",
"getrecordpropertyvalue": null
}
]

Answer 1

Please change you query to use single quotes around 'Response-Body'. In SQL double quotes are used to escape column names (similar to []) so you query is interpreted as column with name "Response-Body" instead of string constant "Response-Body"
SELECT
GetArrayElement(Requests.context.custom.dimensions, 0),
GetType( GetArrayElement(Requests.context.custom.dimensions, 0)),
GetRecordPropertyValue(GetArrayElement(Requests.context.custom.dimensions, 0), 'Response-Body')
INTO
PowerBICreateScheduleDurations
FROM
AppInsightsIncomingRequests AS Requests