Aggregate function (sum) in Value Set - Using CONNECT BY LEVEL - performance issue

Summary:

Hello

When the aggregate function returns a whole number, we can fetch the value from the value set, and even when it returns a decimal, the output is generated correctly. However, the issue is that the extract is taking more than 12 hours to retrieve one month of calculated payroll process data

Here is the used code below;

SELECT
TO_CHAR ((n.n),'FM999999999999990D00')
FROM(SELECT /*+ CONNECT_BY_FILTERING / (LEVEL*0.01) n FROM DUAL CONNECT BY LEVEL <= 1000000000) n

WHERE

n.n = ( inner sql query )

Do you have any suggestions on how we can improve the performance?

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