How to add new data to an existing dataset in EG?

[Andalusia]

This is my current dataset (an example so you can reproduce my case, the real one is much bigger):

data have;
infile datalines truncover;
input type $ model $;
datalines;
XX-1 Light
XX-2 Heavy
XX-3 Heavy
XX-4 Heavy
XX-5 Slim
XX-6 Light
XX-7 Heavy
;

I want to add two lines of data to it:

XX-8 Light
XX-9 Slim

[Kurt_Bremser]

Create a new dataset, and append it:

data have;
infile datalines truncover;
input type $ model $;
datalines;
XX-1 Light
XX-2 Heavy
XX-3 Heavy
XX-4 Heavy
XX-5 Slim
XX-6 Light
XX-7 Heavy
;

data new;
infile datalines truncover;
input type $ model $;
datalines;
XX-8 Light
XX-9 Slim
;

proc append
  base=have
  data=new
;
run;