In this example we summerize the source datas into the target object with the
condition that the datas which are merged together have to be came from the same day.
As you see we have selected the Target Object and the Source object for the transformation.
We also seleceted a group by entry, but this step is optional.

On the Target ID formula tabsheet, we calculate the day of the current data.
And we try to decide if we have corresponding target record for the current source record.
If we were not able to find one, then we return with minus one, this way it will create a
new record for us.

In the transformation we calculate the summery of the amount of the current day, by
adding the current amount to the existing amount.
