Oracle 11g Release 2

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CREATE TABLE table_name ( "DATE", Bill_No, Amount ) AS
SELECT DATE '2019-07-24' + INTERVAL '12:00:00' HOUR TO SECOND, '43565',  20 FROM DUAL UNION ALL
SELECT DATE '2019-07-24' + INTERVAL '18:00:00' HOUR TO SECOND, '12354', 100 FROM DUAL UNION ALL
SELECT DATE '2019-07-22' + INTERVAL '13:20:02' HOUR TO SECOND, '12782', 120 FROM DUAL UNION ALL
SELECT DATE '2019-07-22' + INTERVAL '15:30:23' HOUR TO SECOND, '99807', 200 FROM DUAL UNION ALL
SELECT DATE '2019-07-21' + INTERVAL '20:00:23' HOUR TO SECOND, '23686',  50 FROM DUAL UNION ALL
SELECT DATE '2019-07-21' + INTERVAL '11:34:45' HOUR TO SECOND, '38965',  10 FROM DUAL UNION ALL
SELECT DATE '2019-07-21' + INTERVAL '10:05:30' HOUR TO SECOND, '04578',  45 FROM DUAL UNION ALL
SELECT DATE '2019-07-20' + INTERVAL '19:30:00' HOUR TO SECOND, '34950',  38 FROM DUAL UNION ALL
SELECT DATE '2019-07-20' + INTERVAL '14:25:00' HOUR TO SECOND, '54954',  25 FROM DUAL
9 rows affected

ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS'
SELECT *
FROM   (
  SELECT *
  FROM   (
    SELECT t.*,
           SUM( Amount )
             OVER ( ORDER BY "DATE" DESC ) AS total
    FROM   table_name t
  )
  WHERE total <= 500
  OR    ROWNUM = 1
  ORDER BY total DESC
)
WHERE ROWNUM = 1


DATE
BILL_NO
AMOUNT
TOTAL


2019-07-21 11:34:45
38965
10
500