PL/SQL cursor question

change select to select distinct

Well I would prefer the first approach, with the single update statement.

You get the ORA-01427 error because the subquery returns more than one rows.
sujit_kumar comment is basically correct: You don't seem to link the subquery with the external statement.
Weel I don't quite agree with the rcrapp1.<Foreign Key> = rprlcrt.<Primary Key> expression. It could be
 rcrapp1.<Primary Key> = rprlcrt.<Foreign Key> as well, but the main idea is that you need a link there.
 

When I add "rcrapp3_pidm = rprlcrt_pidm", I get no records found.  I still think a cursor is necessary because each pidm can have rcrapp3_yr_in_coll_2 value.  For example, one pidm, can have a '2' and a different pidm can have a '2'.  They are both are correct.

I'm in error.  When I run it in my production database, (select only) I get records returned but the rcrapp3_yr_in_call_2 value can be say a '2' for different pidms.  Like my previous post.

OK, lets start from the beginning. Try to give an example:

assume that you have two rows in rprlcrt, one has pidms=1 and the other pidms=2. The both have  rprlcrt_cint_code IS NULL AND rprlcrt_cert_date IS NULL.

TO what value to you want to set rprlcrt_clas_code in each case?

If you can try the following in your production environment:

SELECT 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 rcrapp3_pidm = rprlcrt_pidm) new_rprlcrt_clas_code
FROM rprlcrt
 WHERE rprlcrt_cint_code IS NULL AND rprlcrt_cert_date IS NULL;

Does it run or do you get an error? If not does it return any value or do you get null?

I want to set it to the matching value in the rcrapp3 table "rcrapp3_yr_in_coll_2".
When I run your code in production I get 214 records, some have blank new_rprlcrt_clas_codes.
When I run
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'
I get over 2400 records.

The key is "matching value in the rcrapp3 table" How do you match it?
Is it with "rcrapp3_pidm = rprlcrt_pidm" ? If yes then is it possible that you don't have a matching row for some cases?

Since you get 214 records with my query, then those rows have
prlcrt_cint_code IS NULL AND rprlcrt_cert_date IS NULL
Since some rows have null in new_rprlcrt_clas_codes, then for those rows there was no matching row  found in rcrapp3 table. If that is acceptable, then your update statement should be (I think you already tried it):

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 rcrapp3_pidm = rprlcrt_pidm)
 WHERE rprlcrt_cint_code IS NULL AND rprlcrt_cert_date IS NULL;

I've updated my cursor:

/* Formatted on 2007/08/01 11:58 (Formatter Plus v4.8.6) ECSU-Admin Computing */
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;

      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);

      EXIT WHEN c_select_pidm%NOTFOUND;
   END LOOP;

   CLOSE c_select_pidm;
END;