请教一个数据类型的问题。

试试用嵌套表:
type tssn is table of number(10);
type tfname is table of varchar2(50);....FOR singleclient IN client_cur
    LOOP
       ssn.extend;
       fname.extend;
       ssn(percount) := singleclient.clientid;
       fname(percount) := singleclient.clientname;
       dbms_output.put_line(ssn(percount));
       percount := percount + 1;
    END LOOP;