create or replace
function get_list(p_mainkey in varchar2)
    return varchar2
    is
        --Use AT to avoid mutating table error in trigger
    	pragma autonomous_transaction;
    	l_str  varchar2(2000) default null;
        l_sep varchar2(1) default null;
   begin
        for x in ( select articleno from specific where mainkey = p_mainkey and artictype like 'artwork%') loop
           l_str := l_str || l_sep || x.articleno;
          
            l_sep:=',';
           
       end loop;
       return l_str;
   end;
/ 


--the trigger that does the job.
CREATE OR REPLACE TRIGGER tr_artwork_tomain
BEFORE INSERT OR UPDATE ON "SPECIFIC"
FOR EACH ROW
BEGIN
   --Copy a Search list to main based an artwork number...
    update styles set moc060=get_list(:new.mainkey) where mainkey=:new.mainkey;
 END;
/