ORA-01002: fetch out of sequence

ORA-01002: fetch out of sequence

错误定位：
 
SQL> !oerr ora 01002
 01002, 00000, "fetch out of sequence"
 // *Cause: This error means that a fetch has been attempted from a cursor
 //        which is no longer valid.  Note that a PL/SQL cursor loop
 //        implicitly does fetches, and thus may also cause this error.
 //        There are a number of possible causes for this error, including:
 //        1) Fetching from a cursor after the last row has been retrieved
 //            and the ORA-1403 error returned.
 //        2) If the cursor has been opened with the FOR UPDATE clause,
 //            fetching after a COMMIT has been issued will return the error.
 //        3) Rebinding any placeholders in the SQL statement, then issuing
 //            a fetch before reexecuting the statement.
 // *Action: 1) Do not issue a fetch statement after the last row has been
 //            retrieved - there are no more rows to fetch.
 //          2) Do not issue a COMMIT inside a fetch loop for a cursor
 //            that has been opened FOR UPDATE.
 //          3) Reexecute the statement after rebinding, then attempt to
 //            fetch again.
 
SQL>

查看pl sql：

declare
  cursor emp_cursor is
    select * from emp_text for update;
  v_object_name emp_text%rowtype;
begin
  open emp_cursor;
  loop
    fetch emp_cursor
      into v_object_name;
    if emp_cursor%found then
      update emp_text
        set object_id =
            (emp_seq.nextval)
      where object_name = v_object_name.object_name;
      COMMIT;
    end if;
    exit when emp_cursor%notfound;
  end loop;
  close emp_cursor;
 end;

正确写法：

declare
  cursor emp_cursor is
    select * from emp_text for update;
  v_object_name emp_text%rowtype;
begin
  open emp_cursor;
  loop
    fetch emp_cursor
      into v_object_name;
    if emp_cursor%found then
      update emp_text
        set object_id =
            (emp_seq.nextval)
      where object_name = v_object_name.object_name;
    end if;
    exit when emp_cursor%notfound;
  end loop;
  close emp_cursor;
  COMMIT;
end;