What is a Sigma equivalent of OVER ( partition by ) for a window function?

Hello! Is it possible to specify the grouping for the First function? I want to do something like First(Campaign) OVER (Partition By LeadId) ORDER BY CreatedDate.

With Sigma, we have a slightly different approach. We have levels in a worksheet, and, once you create a level for a Lead (by LeadId), you will be able to place the First(Campaign) function at that level, and it will have the effect of partitioning over a LeadId. Hope this helps!