Force system.tag.queryTagHistory() to use specific historian db

Ignition
4

When you set up a Database as a Historical Provider it becomes available to the designer, as a selection in the history section of the tag editor (as you know).

If you want to look up history for a tag path on a different provider than what is set in the tag editor, then you will need to manually construct the Historical tag path with the correct Historical Provider.

Here is a little script I adapted that shows how to do it (aside from manual concatenation).

def getHistoricalTagPath(path):
    from com.inductiveautomation.ignition.common import QualifiedPath, WellKnownPathTypes,QualifiedPathUtils
    from com.inductiveautomation.ignition.common.tags.paths.parser import TagPathParser

    qPath = QualifiedPathUtils.fromTagPathNew(TagPathParser.parseSafe('default',path))
    gateway = system.tag.readBlocking('[System]Gateway/SystemName'])
    driver = ':'.join([gateway.value,qPath.getPathComponent('prov')])
    return QualifiedPath.Builder().set(WellKnownPathTypes.HistoryProvider,'YourHistoryProvider').setDriver(driver).setTag(qPath.getPathComponent('tag')).build().toString()

You can find the original script and conversation here:

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