first order date/copy column from multiple tables

Hi Anonymous,

Question 1

If you have created a one to many relationship between user table and order table, you can added a calculated column in order table using this formula.

user added date=related(user[user date])

If you didn't create any relationship between these tables, you can use a LookUpValue function in order table so that it can reference to the user added date column.

user added date = LOOKUPVALUE(user[user date],user[user id],'order'[user id]) 

Question 2

If above solutions can meet your requirement, the master calendar is not required. By the way, what do you mean deal with missing dates? And I am not clear about your second requirement that 'find out count of user’s first order'. Do you want to count the number of each user when they first give an order? If so, how about trying to create a measure like this: 

Count Fisrt order= DISTINCTCOUNT('order'[user id])

If I have something misunderstood, please elaborate your sceond requirement with some sample data and please give an example of your desired output.

Regards,
Yuliana Gu