Oracle 18c

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CREATE TABLE ORDER_TBL
(
  ORDER_PAY   DATE,
  ORDER_ID    VARCHAR2(10 BYTE),
  PRODUCT_ID  VARCHAR2(10 BYTE),
  QUANTITY    NUMBER(5),
  PRICE       NUMBER(5)
)
Insert into ORDER_TBL
   (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_TBL
   (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_TBL
   (ORDER_PAY, ORDER_ID, PRODUCT_ID, QUANTITY, PRICE)
 Values
   (TO_DATE('5/1/2015', 'MM/DD/YYYY'), 'ORD3', 'PROD3', 10, 25);
1 rows affected

Insert into ORDER_TBL
   (ORDER_PAY, ORDER_ID, PRODUCT_ID, QUANTITY, PRICE)
 Values
   (TO_DATE('5/1/2015', 'MM/DD/YYYY'), 'ORD4', 'PROD1', 20, 5);
1 rows affected

Insert into ORDER_TBL
   (ORDER_PAY, ORDER_ID, PRODUCT_ID, QUANTITY, PRICE)
 Values
   (TO_DATE('5/2/2015', 'MM/DD/YYYY'), 'ORD5', 'PROD3', 5, 25);
1 rows affected

Insert into ORDER_TBL
   (ORDER_PAY, ORDER_ID, PRODUCT_ID, QUANTITY, PRICE)
 Values
   (TO_DATE('5/2/2015', 'MM/DD/YYYY'), 'ORD7', 'PROD1', 2, 5);
1 rows affected

Insert into ORDER_TBL
   (ORDER_PAY, ORDER_ID, PRODUCT_ID, QUANTITY, PRICE)
 Values
   (TO_DATE('5/2/2015', 'MM/DD/YYYY'), 'ORD8', 'PROD5', 1, 50);
1 rows affected

Insert into ORDER_TBL
   (ORDER_PAY, ORDER_ID, PRODUCT_ID, QUANTITY, PRICE)
 Values
   (TO_DATE('5/2/2015', 'MM/DD/YYYY'), 'ORD9', 'PROD6', 2, 50);
1 rows affected

Insert into ORDER_TBL
   (ORDER_PAY, ORDER_ID, PRODUCT_ID, QUANTITY, PRICE)
 Values
   (TO_DATE('5/2/2015', 'MM/DD/YYYY'), 'ORD10', 'PROD2', 4, 10);
1 rows affected

Insert into ORDER_TBL
   (ORDER_PAY, ORDER_ID, PRODUCT_ID, QUANTITY, PRICE)
 Values
   (TO_DATE('5/2/2015', 'MM/DD/YYYY'), 'ORD6', 'PROD4', 6, 20);
1 rows affected

SELECT order_pay, product_id, (quantity * price) as sales
          FROM order_tbl
       PIVOT (SUM (sales) FOR order_pay IN ('01-MAY-2015', '02-MAY-2015'))
ORA-00904: "SALES": invalid identifier

SELECT order_pay, product_id, (quantity * price) as sales
          FROM order_tbl
       PIVOT (SUM (quantity * price) FOR order_pay IN ('01-MAY-2015', '02-MAY-2015'))
ORA-00904: "PRICE": invalid identifier

SELECT order_pay, product_id, quantity, price
          FROM order_tbl
       PIVOT (SUM (quantity * price) FOR order_pay IN ('01-MAY-2015', '02-MAY-2015'))
ORA-00904: "PRICE": invalid identifier

SELECT *
FROM (
  SELECT order_pay, product_id, quantity, price
  FROM order_tbl
)
PIVOT (SUM (quantity * price) FOR order_pay IN ('01-MAY-2015', '02-MAY-2015'))


PRODUCT_ID
'01-MAY-2015'
'02-MAY-2015'


PROD1
125
10

PROD4
null
120

PROD3
250
125

PROD5
null
50

PROD2
20
40

PROD6
null
100
PRODUCT_ID	'01-MAY-2015'	'02-MAY-2015'
PROD1	125	10
PROD4	null	120
PROD3	250	125
PROD5	null	50
PROD2	20	40
PROD6	null	100