Prepare the spaetzle in boiling salted water according to the instructions on the packet. Place the white sausage in boiling water, remove the pot from the heat. Let the sausage stand for 8 minutes. Wash chives, dab dry, cut into rings. Mix mustard and vinegar, season with salt, pepper and sugar. Whip oil in a thin stream underneath. Stir in chives.
Drain the sausage and chill cold. Remove sausage skin and cut sausage into slices. Clean, wash, dab dry and cut salad into strips. Clean, wash and slice radishes. Drain the spaetzle, rinse with cold water and drain. Mix all ingredients together and arrange in a bowl