Oracle SQL ORA-06550和PLS-00103错误

Question

在运行本文底部的代码时，我收到以下错误报告。有人可以指出问题所在吗？谢谢您的帮助。

错误报告-

ORA-06550: line 12, column 8: PL/SQL: ORA-00942: table or view does not exist
ORA-06550: line 11, column 3: PL/SQL: SQL Statement ignored
06550. 00000 -  "line %s, column %s:\n%s"
*Cause:    Usually a PL/SQL compilation error.
*Action:

。

SET SERVEROUTPUT ON

DECLARE
  number_of_payments    NUMBER(2);        --Total number of payments
  payment_num           NUMBER(2);           --Current payment number of total
  starting_date         DATE;                  --start date of payment
  ending_due            DATE;                    --due date of payment
  monthly_payment_amt   NUMBER(8,2); --monthly amt due
  donation_balance      NUMBER(8,2);     --remaining balance after pay
  pledgeamt             NUMBER(8,2);            --total amt to pay over term
BEGIN
  SELECT pledgeamt,
         pledgedate,
         paymonths INTO
    pledgeamt,starting_date,number_of_payments
  FROM dd_pledge
  WHERE idpledge = &idpledge;

  monthly_payment_amt := pledgeamt / number_of_payments;
  ending_due := starting_date;
  donation_balance := ( pledgeamt - monthly_payment_amt );
  payment_num := 0;
  LOOP
    payment_num := payment_num + 1;
    ending_due := add_months(ending_due,1);
    dbms_output.put_line('Payment number: '
    || payment_num
    || ' Due Date: '
    || ending_due
    || ' Payment Amount: '
    || monthly_payment_amt
    || ' Balance: '
    || TO_CHAR(donation_balance,'$9999.99') );

    donation_balance := donation_balance - monthly_payment_amt;
    EXIT WHEN donation_balance < 0; --LOOP until condition is met
  END LOOP;

END;