Scan all other rows to match condition

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1

HI,
I need to scan all other rows of 1 column for each and every row of the same column and if condition matches then flag those rows.
EX.
Col1 Col 2 OutputCol
1 1-jan-2020 1
2 5-Mar-2021 1,3
3 4-Dec-2017 Null

In the above ex. for row 1, for date in Col2 will check Col2 for row 2 and 3 and if any date in row 2 & 3 is prior to date in row 1 then flag like OutputCol. Repeate this for row2 &3.
This is very simple case. I have little more complicated condition with large number of records.
Any functions i can use to scan data in each and every row of same or different column to evaluate any condition.

2

For all rows in a table, you can use the InBlock calculation context to check if the count of Col 2 is greater than 1.

However, if you want to try and concatenate all row ids where the comparison holds, that is a complex solution and I’d push it back to the query rather than try and do it in the report.