Question

我代表硬件开发人员问这个问题（我对设备方面的了解不多）。

由于某些原因，由于计划将数据本地存储在设备中并每30分钟发送一次，目前IoT中心每2分钟从设备接收一次数据。但是问题是，数据没有保存到存储中。 2分钟的数据将保存到存储中。但是30分钟的数据不是正确保存到存储中。仅保存数组中的第一个对象。

我正在使用流分析来处理来自IoT中心的数据，并将数据存储到表存储中。

当前消息Json数据（每2分钟）为：

{
    "deviceid": "testdevice12",
    "BatteryVoltage": "31.31",
    "PanelVoltage": "0.00",
    "PanelCurrent": "0.00",
    "OutputVoltage": "31.29",
    "OutputCurrent": "4.94",
    "RSSI": "13",
    "FreeHeapSize": "86.884",
    "timestamp": 1540470493
}

持续30分钟，如下所示：

[{
    "deviceid": "testdevice12",
    "BatteryVoltage": "31.31",
    "PanelVoltage": "0.00",
    "PanelCurrent": "0.00",
    "OutputVoltage": "31.29",
    "OutputCurrent": "4.94",
    "RSSI": "13",
    "FreeHeapSize": "86.884",
    "timestamp": 1540470493
}, {
    "deviceid": "testdevice12",
    "BatteryVoltage": "31.29",
    "PanelVoltage": "0.00",
    "PanelCurrent": "0.00",
    "OutputVoltage": "31.28",
    "OutputCurrent": "4.93",
    "RSSI": "0",
    "FreeHeapSize": "86.884",
    "timestamp": 1540470558
}, {
    "deviceid": "testdevice12",
    "BatteryVoltage": "31.30",
    "PanelVoltage": "0.00",
    "PanelCurrent": "0.00",
    "OutputVoltage": "31.29",
    "OutputCurrent": "4.94",
    "RSSI": "5",
    "FreeHeapSize": "86.884",
    "timestamp": 1540470621
}, {
    "deviceid": "testdevice12",
    "BatteryVoltage": "31.31",
    "PanelVoltage": "0.00",
    "PanelCurrent": "0.00",
    "OutputVoltage": "31.30",
    "OutputCurrent": "4.94",
    "RSSI": "5",
    "FreeHeapSize": "86.884",
    "timestamp": 1540470684
}, {
    "deviceid": "testdevice12",
    "BatteryVoltage": "31.30",
    "PanelVoltage": "0.00",
    "PanelCurrent": "0.00",
    "OutputVoltage": "31.28",
    "OutputCurrent": "4.94",
    "RSSI": "7",
    "FreeHeapSize": "86.884",
    "timestamp": 1540470760
}]

这是我正在使用的ASA查询：

WITH [StreamData] AS ( SELECT * FROM [IoTHubStream] WHERE [ObjectType] IS NULL -- Filter out device info and command responses ) 
SELECT IoTHub.ConnectionDeviceId AS DeviceId, PanelVoltage, PanelCurrent, BatteryVoltage, BatteryCurrent, OutputVoltage, OutputCurrent, Temperature, Humidity, EventProcessedUtcTime, PartitionId, EventEnqueuedUtcTime, * INTO [DeviceDataHistory] FROM [StreamData]

Answer 1

最终得到它。有几点： 1.具有缓存数据结构的JSON有效负载应具有以下结构：

{
 "topic": "cachedData",
  "deviceId": "testdevice12",
  "data":
[{
"BatteryVoltage": "31.31",
"PanelVoltage": "0.00",
"PanelCurrent": "0.00",
"OutputVoltage": "31.29",
"OutputCurrent": "4.94",
"RSSI": "13",
"FreeHeapSize": "86.884",
"timestamp": 1540470493
}, {
"BatteryVoltage": "31.29",
"PanelVoltage": "0.00",
"PanelCurrent": "0.00",
"OutputVoltage": "31.28",
"OutputCurrent": "4.93",
"RSSI": "0",
"FreeHeapSize": "86.884",
"timestamp": 1540470558
}, {
"BatteryVoltage": "31.30",
"PanelVoltage": "0.00",
"PanelCurrent": "0.00",
"OutputVoltage": "31.29",
"OutputCurrent": "4.94",
"RSSI": "5",
"FreeHeapSize": "86.884",
"timestamp": 1540470621
}, {
"BatteryVoltage": "31.31",
"PanelVoltage": "0.00",
"PanelCurrent": "0.00",
"OutputVoltage": "31.30",
"OutputCurrent": "4.94",
"RSSI": "5",
"FreeHeapSize": "86.884",
"timestamp": 1540470684
}, {
"BatteryVoltage": "31.30",
"PanelVoltage": "0.00",
"PanelCurrent": "0.00",
"OutputVoltage": "31.28",
"OutputCurrent": "4.94",
"RSSI": "7",
"FreeHeapSize": "86.884",
"timestamp": 1540470760
}]
}

Azure流分析应如下所示：

 SELECT   
  iothubAlias.deviceId,
  arrayElement.ArrayValue.BatteryVoltage,
  arrayElement.ArrayValue.PanelVoltage,
  arrayElement.ArrayValue.PanelCurrent,
  arrayElement.ArrayValue.OutputVoltage,
  arrayElement.ArrayValue.OutputCurrent,
  arrayElement.ArrayValue.RSSI,
  arrayElement.ArrayValue.FreeHeapSize,
  arrayElement.ArrayValue.timestamp
INTO [DeviceDataHistory]
FROM [IoTHubStream] as iothubAlias  
CROSS APPLY GetArrayElements(iothubAlias.data) AS arrayElement

要从输入中检索多行，您必须使用“ GetArrayElements”-您可以在此处阅读更多内容：

https://docs.microsoft.com/en-us/azure/stream-analytics/stream-analytics-parsing-json

https://msdn.microsoft.com/en-US/azure/stream-analytics/reference/getarrayelements-azure-stream-analytics

记住将Azure表集的PartitionKey和RowKey设置为Azure流分析的输出：

最终结果如下：

尝试并让我知道是否有帮助。

是否可以将大型JSON数据发送到IoT中心？

1 个答案: