Communication between records

CloverDX Platform
1

I’m trying to build a graph to cleanse some datalogging files which are the result of collecting data from temperature sensors. Sometimes there’s a hiccup in the collection and we get a null value from the sensor. In this case, we want to replace the null with the value from the previous record. How can I do this within Clover, please?

2

Hi Bob,

There is few options how you can remember data of previous records while passing through transformation components, e.g. Reformat:

  1. store previous values in dictionary - http://doc.cloveretl.com/documentation/ … -ctl2.html

  2. define “global” variable which can hold data during whole transformation run


//#CTL2

integer lastValue;

function integer transform() {
	//current value not null
	if ($in.0.value!=null) {
		//send to output
		$out.0.value = $in.0.value;

		//update last non-null value
		lastValue = $in.0.value;
	} else {
		//use last non-null value for output
		$out.0.value = lastValue;
	}

	return ALL;
}

For both approaches you may use map/list datatype, see http://doc.cloveretl.com/documentation/ … -ctl2.html for details.