def valueChanged(tag, tagPath, previousValue, currentValue, initialChange, missedEvents): """ Fired whenever the current value changes in value or quality. Arguments: tag: The source tag object. A read-only wrapper for obtaining tag properties. tagPath: The full path to the tag (String) previousValue: The previous value. This is a "qualified value", so it has value, quality, and timestamp properties. currentValue: The current value. This is a "qualified value", so it has value, quality, and timestamp properties. initialChange: A boolean flag indicating whether this event is due to the first execution or initial subscription. missedEvents: A flag indicating that some events have been skipped due to event overflow. """ var = system.tag.read("[.]/Querry") data = system.dataset.toPyDataSet(var.value) system.tag.write("[.]/Data/Lots", data)
So i need to read the querry tag and append only the first row of memory tag.