Store and Read exact data from Historian

Ignition
1

I have a data acquisition application, using transaction group, is not really so efficient, so looking back at historizing tag.

Say that I have two ignition tag, which data comes from two pressure sensors.
For testing application, on data change, I want Ignition to record exact data into historian
When being query on perspective, i need exact data as stored to be read. (I understood that on reading these data, ignition may perform operation on the data if desired.)

Regardless of tag history setting (deadband style, etc).
Does Ignition store data in historian exactly as what the data at that moment?

Background:
I have setup transaction group to record 40 sensors when triggered.

  1. On transaction group trigger, we record each data from 40 sensors, data have changed or not.
    (thus not storage efficient..?)
  2. When charting, chart component will crash because of so many data
2

The tag historian does not synchronize storage of multiple tags. Each tag is solo, and recorded separately.

If you need multiple tag values recorded together, then SQL Bridge transaction groups are the right tool, or you can script an SQL insert.

3

Yes, but I can query multiple tag history by using queryTagHistory with wide format? yeah?

Instead of this, was thinking, during measurement, get the startDatetime and endDatetime, then use queryTagHistory, wouldn’t this work as well?

4

You should experiment. I doubt you'll like this.

Good luck.