Determine number of records availble in a ThingSpeak channel

조회 수: 5 (최근 30일)
DL KA
DL KA 2020년 11월 26일
댓글: Christopher Stapels 2020년 12월 11일
Using the REST API, I would like to be able to query for the number of records of data stored in a ThingSpeak channel before reading that data.
Is there a way to do this?
  댓글 수: 2
Vinod
Vinod 2020년 11월 30일
Can you tell me more about your application? Say you have the number of records stored, what do you intend to do with this data?
DL KA
DL KA 2020년 11월 30일
I need to make decisions based on the number of records available before I read the quantity of records I need to operate on.

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답변 (1개)

Vinod
Vinod 2020년 12월 3일
편집: Vinod 2020년 12월 3일
I'd recommend the best solution is to retrieve data based on date range. Again, keep in mind the response will contain at most 8000 points. So, you will want to pick your date range based on how frequently your channel is updated. See more details here.
  댓글 수: 3
Vinod
Vinod 2020년 12월 3일
Actually, the REST API doc I linked to does take you to this page - reading the last entry in a channel. If you look at the JSON example there, you will see "entry_id" is a returned paramter. While I do mention it here as a direct response to your question, I strongly suggest not relying on the last entry_id. I was trying to point you to a better solution based on your decription.
Christopher Stapels
Christopher Stapels 2020년 12월 11일
You could also update the channel and look at the response. ThingSpeak returns the number of records in the channel However, after you update the channel to see if there is anything in it, you would have to clear it again or it would look like there are records in the channel. :)

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