Oracle 18c

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CREATE TABLE ORDER_TBL2
(
  ORDER_PAY   DATE,
  ORDER_ID    VARCHAR2(10 BYTE),
  PRODUCT_ID  VARCHAR2(10 BYTE),
  QUANTITY    NUMBER(5),
  PRICE       NUMBER(5)
);
Insert into ORDER_TBL2
   (ORDER_PAY, ORDER_ID, PRODUCT_ID, QUANTITY, PRICE)
 Values
   (TO_DATE('5/1/2015', 'MM/DD/YYYY'), 'ORD1', 'PROD1', 5, 5);
1 rows affected

Insert into ORDER_TBL2
   (ORDER_PAY, ORDER_ID, PRODUCT_ID, QUANTITY, PRICE)
 Values
   (TO_DATE('5/1/2015', 'MM/DD/YYYY'), 'ORD2', 'PROD2', 2, 10);
1 rows affected

Insert into ORDER_TBL2
   (ORDER_PAY, ORDER_ID, PRODUCT_ID, QUANTITY, PRICE)
 Values
   (TO_DATE('5/1/2015', 'MM/DD/YYYY'), 'ORD3', 'PROD3', 3, 25);
1 rows affected

WITH
    cte (order_id,
         product_id,
         quantity,
         cnt)
    AS
        (SELECT order_id,
                product_id,
                1 as quantity,
                1 as cnt
           FROM order_tbl2        
         UNION ALL
         SELECT a.order_id,
                a.product_id,
                b.quantity,
                b.cnt + 1
           FROM order_tbl2 A INNER JOIN cte b ON a.product_id = b.product_id
          WHERE  b.cnt + 1 < a.quantity)
SELECT order_id, product_id, quantity
  FROM cte;
ORA-32044: cycle detected while executing recursive WITH query

WITH
    cte (order_id,
         product_id,
         quantity,
         cnt)
    AS
        (SELECT order_id,
                product_id,
                1 as quantity,
                1 as cnt
           FROM order_tbl2        
         UNION ALL
         SELECT a.order_id,
                a.product_id,
                b.quantity,
                b.cnt + 1
           FROM order_tbl2 A INNER JOIN cte b
             ON a.order_id = b.order_id
            AND a.product_id = b.product_id
          WHERE  b.cnt + 1 < a.quantity)
SELECT order_id, product_id, quantity
  FROM cte;
ORA-32044: cycle detected while executing recursive WITH query

WITH
    cte (order_id,
         product_id,
         quantity,
         cnt)
    AS
        (SELECT order_id,
                product_id,
                quantity,
                1 as cnt
           FROM order_tbl2        
         UNION ALL
         SELECT b.order_id,
                b.product_id,
                b.quantity,
                b.cnt + 1
           FROM cte b
          WHERE  b.cnt < b.quantity)
SELECT order_id, product_id, 1 as quantity
  FROM cte
ORDER BY order_id, product_id;


ORDER_ID
PRODUCT_ID
QUANTITY


ORD1
PROD1
1

ORD1
PROD1
1

ORD1
PROD1
1

ORD1
PROD1
1

ORD1
PROD1
1

ORD2
PROD2
1

ORD2
PROD2
1

ORD3
PROD3
1

ORD3
PROD3
1

ORD3
PROD3
1


WITH
    cte (order_id,
         product_id,
         real_quantity,
         quantity,
         cnt)
    AS
        (SELECT order_id,
                product_id,
                quantity as real_quantity,
                1 as quantity,
                1 as cnt
           FROM order_tbl2        
         UNION ALL
         SELECT b.order_id,
                b.product_id,
                b.real_quantity,
                b.quantity,
                b.cnt + 1
           FROM cte b
          WHERE  b.cnt < b.real_quantity)
SELECT order_id, product_id, quantity
  FROM cte
ORDER BY order_id, product_id;


ORDER_ID
PRODUCT_ID
QUANTITY


ORD1
PROD1
1

ORD1
PROD1
1

ORD1
PROD1
1

ORD1
PROD1
1

ORD1
PROD1
1

ORD2
PROD2
1

ORD2
PROD2
1

ORD3
PROD3
1

ORD3
PROD3
1

ORD3
PROD3
1
ORDER_ID	PRODUCT_ID	QUANTITY
ORD1	PROD1	1
ORD1	PROD1	1
ORD1	PROD1	1
ORD1	PROD1	1
ORD1	PROD1	1
ORD2	PROD2	1
ORD2	PROD2	1
ORD3	PROD3	1
ORD3	PROD3	1
ORD3	PROD3	1