datediff for first dates

[Ley022]

Hi,

I want to calculate the time difference (datediff) in days between two dates: Timestamp and Date (blue). But I want to calculate this difference for the first date of date, for every IDs. If it is not the first date, it should return an empty value.

An example:

Thanks in advance

[amitchandak]

@Ley022 , Logic is not very clear.

You can try like

new column =
var _min = minx(filter(table,[Id] =earlier([ID])),[Date])
return
if([Date]=_min , datediff([date], [timestamp], day), blank())