SQL & PL/SQL

Hi all,
Please advice me what is wronge with this
ORA-00904: "NONE": invalid identifier


create or replace trigger test_table2
before insert
on Ta
for each row
declare
v2_none_con varchar2(20);
v2_none_con2 varchar2(20);
i number(10);
TYPE v2_EmpCurTyp IS REF CURSOR;
v2_emp_cursor v2_EmpCurTyp;
v2_stmt_str VARCHAR2(200);
TYPE v2_employee_type IS RECORD ( v_rowid varchar(100));
v2_emp_content v2_employee_type;
begin

v2_none_con2:='NONE';

v2_stmt_str := 'select rowid from t1 where name='v2_none_con2;
i:=0;
OPEN v2_emp_cursor FOR v2_stmt_str ;
LOOP FETCH v2_emp_cursor INTO v2_emp_content;
EXIT WHEN v2_emp_cursor%NOTFOUND;
dbms_output.put_line(v2_emp_content.v_rowid);
i:=i+1;
v2_none_con:='NON'||to_char(i);

END LOOP;
end;




SQL> /
insert into ta values(10,' Wael')
*
ERROR at line 1:
ORA-00904: "NONE": invalid identifier
ORA-06512: at "FINAL.TEST_TABLE2", line 15
ORA-04088: error during execution of trigger 'FINAL.TEST_TABLE2'


SQL>