Can someone help me with some set analysis please?

[samvile18]

Hi everyone - I'm trying to count the amount of logins in a 30 day window after a campaign my campaign date. So essentially, count the amount of logins that occur within 30 days of the CampaignDate. 

My data model looks like this, it's joined at %Master_Id:

I'm struggling to get the syntax to work for the set analysis...can anyone help me please?

[SterreKapteijns]

I am not really sure what the Master_Id field represents.. but if the Master_Id is the unique login ID:

count({< LoginDate = {"=LoginDate >= CampaignDate and LoginDate <= CampaginDate + 30" } >} distinct %Master_Id)