add identifier attribute for joining datasets

Lin_Wei

data set A:

a1,b1,c1

a2,b2,c2

data set B:

x1,y1,z1

x2,y2,z2

right now I am manually adding a final row column of data after exporting; for which dataset the data came from ie:
data set A:

a1,b1,c1,setA

a2,b2,c2,setA

data set B:

x1,y1,z1,setB

x2,y2,z2,setB

before joining them together, Im wondering if there is a way to do that using join or create attribute removing the need for me to run another procress just to join the data after i manually key in the new data

Lin_Wei

Im stupid lol just generate attribtue