Join all files in a directory

Question

How can I join all of the files in a directory. I can do it in one step by explicitly naming the files below, is there a way to do it without explicitly naming the files?

Answer 1

use awk, say you want to join on 1st field

awk '{a[$1]=a[$1] FS $0}END{for(i in a) print i,a[i]}' file*