Query Tag History: Retrieve Only Timestamps

General Discussion
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1

Hello,

I am using system.tag.queryTagHistory() and I have stored large JSON/FFT string data in tag history. When I query these tags over a long time range, the query becomes very slow because of the large string values.

What I really need at first is only the t_stamp column, so that I can later fetch the actual data on demand when the user selects a timestamp.

Is there a way to query only the t_stamp values from history (without pulling the string column), or is there a recommended approach for handling this use case?

If anyone has a solution or workaround, please share.

Thanks in advance ! :slightly_smiling_face:

2

Hm for this specific use case, I would rather use a custom SQL table to hold the data instead of the built-in tag historian…

I’m honestly not sure there is a way to get only the timestamps.

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