building e(etage/floor). axis x-y where x is int and y char 1-A .. 12-I table axis ( r integer primary key -- is rowid e integer x integer y varchar -- i tried 'char' and 'text' before ) i check for (0,1,"A"). does not exists and i insert. check again. ok rowid=1 i check for (0,1,"B"). does not exists and i insert. check again. ok rowid=2 i check for (0,1,"C") and it finds rowid 1 and 2. so (*,*,C) is not inserted. i check for (*,*,"x") with x unequal C works. for all e,x the same. now, i use integer for y too and use something like i=ord(c) c=chr(i) to convert, but i like to know. thanks in advance, Andreas