COUNTAX with related tables

[IvanMislav]

Here is the situation. I have two tables: "Messages" and "Users" which are related throught User_id.

Mesagges: Message_id, User_id

Users: User_id, User_name, Department

What i want to do is to create a measure (messagesMarketing) which will count the number of Message_id (it can be COUNTROWS function since message_id are unique values) filtered by users in Department = "Marketing".

Can anyone help me with this, please?

[samdthompson]

Hi. The way you describe the data it sounds like its already got the relationship. If thats not the case then make the relationship - in relationship view drag Messages[user_id] onto User[user_id]

Then on the messages table write the measure. messagesMarketing=countrows(message_id)

Then in report builder drag your measure on to the canvas and your marketing department onto the canvas (make slicer). The slicer will now return the countrows of messages for any selected department.

//if this is a solution to your problem please mark as such

[IvanMislav]

Thx for the answer but it's not what I need. I need to create measure for each department separately because i want to show the data with Heatmap custom visual, and it cannot be done the same way as, for example Matrix visual. 

[samdthompson]

ok what about:

=CALCULATE(COUNTROWS(messageid, filter(deparment)="department1")

=CALCULATE(COUNTROWS(messageid, filter(deparment)="department2")

...

=CALCULATE(COUNTROWS(messageid, filter(deparment)="department n")

[IvanMislav]

Thanks Sam, 

I finally figured it out. I just needed to slightly modify your suggestion.

When i tried...

= CALCULATE(COUNTROWS('Messages', FILTER(Users,Users[Department]="department1")))

This gives me an error saying "Too many arguments were passed to the COUNTROWS function". So i made a separate measure Count of messages= COUNTROWS('Messages') and then i used that mesure for my formula.

Department 1 = CALCULATE([Count of messages],FILTER(Users,Users[Department]="Department 1"))

Now it works like a charm

[samdthompson · Accepted solution]

Hey, I realised my formula was incorrect as I had missed out the parenthesis for the countrows portion. It should have read:

=CALCULATE(COUNTROWS(messageid), filter(deparment)="department1")

=CALCULATE(COUNTROWS(messageid), filter(deparment)="department2")

...

=CALCULATE(COUNTROWS(messageid), filter(deparment)="department n")