Appreciate your advice

I am really a fresher in DB2 domain, not quite sure any simpler way to process this translation. at present, I try to redirect to query to Unix file. Unfortunately, I dunno how to specify the delimiter, as you know, query result always delimit by space, can I use another delimiter ?
By the way, we can use || to concatenate two column, but if one column = null, the whole record is null which is not allowed in requirement.
Any advice?