Question : PL/SQL cursor question

I am trying to correct this PL/SQL code (9i database) to update correctly.  I am getting the error ORA-01427: single-row subquery returns more than one row because there can be the same value for rcrapp3_yr_in_coll_2 for different rcrapp1_pidms/rcrapp3_pidms.

UPDATE rprlcrt
   SET rprlcrt_clas_code =
          (SELECT rcrapp3_yr_in_coll_2
                      FROM rcrapp3, rcrapp1
                     WHERE rcrapp1_curr_rec_ind = 'Y'
                       AND RCRAPP1_INFC_CODE = 'EDE'
                       AND RCRAPP1_INFC_CODE = RCRAPP3_INFC_CODE
                       AND RCRAPP1_SEQ_NO = RCRAPP3_SEQ_NO
                       AND rcrapp1_aidy_code = '0708'
                       AND rcrapp1_pidm = rcrapp3_pidm
                       AND rcrapp3_aidy_code = '0708'
                       AND rcrapp3_yr_in_coll_2 <> '0')
 WHERE rprlcrt_cint_code IS NULL AND rprlcrt_cert_date IS NULL;
*********************************************************************************************************************************
I guess I need a cursor to cycle thru the table RPRLCRT for each ID and update with the nested subquery.  Here is my attempt to write a cursor.  Please advise

CREATE OR REPLACE PROCEDURE update_loans_1
IS
  v_rprlcrt_pidm  NUMBER;
  CURSOR c_select_pidm
  IS
     SELECT rprlcrt_pidm
      FROM RPRLCRT
     WHERE rprlcrt_cint_code IS NULL AND rprlcrt_cert_date IS NULL;

BEGIN
    OPEN c_select_pidm;

    LOOP
       FETCH c_select_pidm
          INTO v_rprlcrt_pidm;
            SELECT rcrapp3_yr_in_coll_2
                      FROM rcrapp3, rcrapp1
                     WHERE rcrapp1_curr_rec_ind = 'Y'
                       AND RCRAPP1_INFC_CODE = 'EDE'
                       AND RCRAPP1_INFC_CODE = RCRAPP3_INFC_CODE
                       AND RCRAPP1_SEQ_NO = RCRAPP3_SEQ_NO
                       AND rcrapp1_aidy_code = '0708'
                       AND rcrapp1_pidm = rcrapp3_pidm
                       AND rcrapp3_aidy_code = '0708'
                       AND rcrapp3_yr_in_coll_2 <> '0'
                       AND rcrapp1_pidm = v_rprlcrt_pidm;
                       COMMIT;
            EXIT WHEN c_select_pidm%NOTFOUND;
     END LOOP;
END;

Answer : PL/SQL cursor question

Why do you insist on the cursor? The single update statement should be faster and the code is simpler.

Anyway, if you want to use the cursor, your code is NOT correct:
You loop within the cursor, but you update the entire table:

UPDATE rprlcrt
         SET rprlcrt_clas_code =
                (SELECT rcrapp3_yr_in_coll_2
                   FROM rcrapp3, rcrapp1
                  WHERE rcrapp1_curr_rec_ind = 'Y'
                    AND rcrapp1_infc_code = 'EDE'
                    AND rcrapp1_infc_code = rcrapp3_infc_code
                    AND rcrapp1_seq_no = rcrapp3_seq_no
                    AND rcrapp1_aidy_code = '0708'
                    AND rcrapp1_pidm = rcrapp3_pidm
                    AND rcrapp3_aidy_code = '0708'
                    AND rcrapp3_yr_in_coll_2 <> '0'
                    AND rcrapp1_pidm = v_rprlcrt_pidm);

If you want to use the cursor then if rprlcrt_pidm is unique in rprlcrt change the update statement to:
Why do you insist on the cursor? The single update statement should be faster and the code is simpler.

Anyway, if you want to use the cursor, your code is NOT correct:
You loop within the cursor, but you update the entire table:

UPDATE rprlcrt
         SET rprlcrt_clas_code =
                (SELECT rcrapp3_yr_in_coll_2
                   FROM rcrapp3, rcrapp1
                  WHERE rcrapp1_curr_rec_ind = 'Y'
                    AND rcrapp1_infc_code = 'EDE'
                    AND rcrapp1_infc_code = rcrapp3_infc_code
                    AND rcrapp1_seq_no = rcrapp3_seq_no
                    AND rcrapp1_aidy_code = '0708'
                    AND rcrapp1_pidm = rcrapp3_pidm
                    AND rcrapp3_aidy_code = '0708'
                    AND rcrapp3_yr_in_coll_2 <> '0'
                    AND rcrapp1_pidm = v_rprlcrt_pidm)
WHERE rprlcrt_pidm = v_rprlcrt_pidm;

Another approach is (If rprlcrt_pidm is not unique)
CREATE OR REPLACE PROCEDURE update_loans_1
IS
   v_rprlcrt_pidm   NUMBER;
   v_rowid ROWID;
   CURSOR c_select_pidm
   IS
      SELECT rprlcrt_pidm, rowid
        FROM rprlcrt
       WHERE rprlcrt_cint_code IS NULL AND rprlcrt_cert_date IS NULL;
BEGIN
   OPEN c_select_pidm;

   LOOP
      FETCH c_select_pidm
       INTO v_rprlcrt_pidm, v_rowid;

      UPDATE rprlcrt
         SET rprlcrt_clas_code =
                (SELECT rcrapp3_yr_in_coll_2
                   FROM rcrapp3, rcrapp1
                  WHERE rcrapp1_curr_rec_ind = 'Y'
                    AND rcrapp1_infc_code = 'EDE'
                    AND rcrapp1_infc_code = rcrapp3_infc_code
                    AND rcrapp1_seq_no = rcrapp3_seq_no
                    AND rcrapp1_aidy_code = '0708'
                    AND rcrapp1_pidm = rcrapp3_pidm
                    AND rcrapp3_aidy_code = '0708'
                    AND rcrapp3_yr_in_coll_2 <> '0'
                    AND rcrapp1_pidm = v_rprlcrt_pidm)
       WHERE rowid = v_rowid;

      EXIT WHEN c_select_pidm%NOTFOUND;
   END LOOP;

   CLOSE c_select_pidm;
END;

PS: And don't forget the commit at the end :)