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Query to see the MAX value in Oracle

I have the following N:N table (which stores the people boardings) in my Oracle Database (it is about an airport):

CREATE TABLE boardings(
Passport VARCHAR2(8),
Day DATE,
Flight VARCHAR2(8),
LuggageWeight NUMBER(4,2),
CONSTRAINT pk PRIMARY KEY(Passport, Day, Flight));

And I would like to make a query in order to see for each flight, which has been the day that has transported the highest amount of weight (keep in mind that a same flight, as RY-1234-VY for example, can make different travels in different days. I have been trying something like this, but it doesn’t work:

SELECT Day, Flight
FROM test
GROUP BY Day, Flight
HAVING SUM(LuggageWeight) = (SELECT MAX(SUM(LuggageWeight))
                             FROM test
                             GROUP BY Day, Flight);

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Answer

I think you were close.

SELECT Day, Flight
FROM boardings b1
GROUP BY Day, Flight
HAVING SUM(LuggageWeight) = (SELECT MAX(SUM(LuggageWeight))
                             FROM boardings b2
                             where b1.Flight = b2.Flight -- I have added this line
                             GROUP BY day, flight);

Here is a demo

Something like this? :

SELECT Flight, Day
FROM boardings b1
where (Flight, Day) = (SELECT Flight, Day
                     FROM boardings b2
                     where b2.flight = b1.flight
                     GROUP BY Flight, Day
                     order by SUM(LuggageWeight) desc
                     fetch first 1 rows only)
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