oracle apex beginner tutorial - 3 || How to Create Dashboard in Oracle Apex

Code:
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Select to_char(o.ORDER_TIMESTAMP,'Mon dd,yyyy') OrderDay,
sum(o.ORDER_TOTAL) sales
from demo_orders o
group by to_char(o.ORDER_TIMESTAMP,'Mon dd,yyyy'),order_timestamp
order by 2 desc nulls last
fetch first 5 rows only;