SELECT [US Platinum].[Mailing Date], Sum([US Platinum].[Unique click], [US Brown.Unique Click], [US Gold.Unique Click] [US GameClub.Unique Click]) AS sum[SumOfUnique click1]
FROM [US Brown], [US GameClub], [US Gold], [US Platinum]
GROUP BY [US Platinum].[Mailing Date];
This is a query written...