Oracle 18c

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CREATE TABLE DD_DONOR (
IDDONOR            NUMBER(4) NOT NULL,
FIRSTNAME          VARCHAR2(15), 
LASTNAME           VARCHAR2(30),
TYPECODE           CHAR(1)
)
CREATE TABLE DD_PLEDGE (
IDDONOR              NUMBER(4),
PLEDGEAMT            NUMBER(8,2)
)
INSERT ALL
  INTO dd_donor ( iddonor, firstname, lastname, typecode ) VALUES ( 1, 'Alice', 'Adams', 'I' )
  INTO dd_donor ( iddonor, firstname, lastname, typecode ) VALUES ( 2, 'Brooke', 'Bryce', 'I' )
  INTO dd_pledge ( iddonor, pledgeamt ) VALUES ( 1, 251.00 )
  INTO dd_pledge ( iddonor, pledgeamt ) VALUES ( 2, 250.01 )
SELECT * FROM DUAL;
4 rows affected

DECLARE
  TYPE dtype_amount IS RECORD (
    typecode DD_DONOR.TYPECODE%TYPE,
    amount   DD_PLEDGE.PLEDGEAMT%TYPE
  );

  CURSOR donnor_pledge (p_typeamount dtype_amount ) IS
    SELECT d.FIRSTNAME,
           d.LASTNAME,
           p.PLEDGEAMT
    FROM   DD_DONOR d
           INNER JOIN DD_PLEDGE p
           USING (IDDONOR)
    WHERE d.TYPECODE  = p_typeamount.typecode
    AND   p.PLEDGEAMT > p_typeamount.amount;

  p_typeamount dtype_amount;
  p_name_amount donnor_pledge%ROWTYPE;
BEGIN
  p_typeamount.typecode := 'I';
  p_typeamount.amount   := 250;
  OPEN donnor_pledge(p_typeamount);
  LOOP
    FETCH donnor_pledge INTO p_name_amount;
    EXIT WHEN donnor_pledge%NOTFOUND;
    DBMS_OUTPUT.PUT_LINE('Donor name: ' || p_name_amount.FIRSTNAME || ' ' || p_name_amount.LASTNAME);
    DBMS_OUTPUT.PUT_LINE('Pledge amount: ' || p_name_amount.PLEDGEAMT);
  END LOOP;
  CLOSE donnor_pledge;    
END;
/
1 rows affected

dbms_output:
Donor name: Alice Adams
Pledge amount: 251
Donor name: Brooke Bryce
Pledge amount: 250.01

DECLARE
  CURSOR donnor_pledge (p_typecode CHAR, p_amount NUMBER ) IS
    SELECT d.FIRSTNAME,
           d.LASTNAME,
           p.PLEDGEAMT
    FROM   DD_DONOR d
           INNER JOIN DD_PLEDGE p
           USING (IDDONOR)
    WHERE d.TYPECODE  = p_typecode
    AND   p.PLEDGEAMT > p_amount;
  
  p_name_amount donnor_pledge%ROWTYPE;
BEGIN
  OPEN donnor_pledge('I', 250);
  LOOP
    FETCH donnor_pledge INTO p_name_amount;
    EXIT WHEN donnor_pledge%NOTFOUND;
    DBMS_OUTPUT.PUT_LINE('Donor name: ' || p_name_amount.FIRSTNAME || ' ' || p_name_amount.LASTNAME);
    DBMS_OUTPUT.PUT_LINE('Pledge amount: ' || p_name_amount.PLEDGEAMT);
  END LOOP;
  CLOSE donnor_pledge;    
END;
/
1 rows affected

dbms_output:
Donor name: Alice Adams
Pledge amount: 251
Donor name: Brooke Bryce
Pledge amount: 250.01