Skip to main content
cancel
Showing results for 
Search instead for 
Did you mean: 

Get certified in Microsoft Fabric—for free! For a limited time, the Microsoft Fabric Community team will be offering free DP-600 exam vouchers. Prepare now

Reply
CNENFRNL
Community Champion
Community Champion

Mechanism of filter propagation in default matrix viz

Dear gurus,

As a frequent user of DAX, I understand fundamental mechanism of filter propagation, say from one side to * side along a 1:* relationship, or cross filter via bi-directional relationship, etc.

Nevertherless, I didn't wrap my head around such a seemingly-natual effect of matrix in terms of filter propagation; I can't even pinpoint keywords to google...😅 so I turn to you for help. TIA!

My mockup data model is simple enough

Untitled.png

Then I drag columns from dimensional tables dDate[Date], dRep[Rep], dProd[PID] into rows of matrix viz, very natually, the default viz shows like this,

Screenshot 2020-10-16 145905.png

To my understanding, the default viz means dDate filters dRep/dProd; but theoretically, fundamental filter propagation( from 1 to * ) doesn't take effect ( maybe I'm totally wrong ) among these dimensional tables. And what's the mysterious power behind the scene?

Here's the dummy file at your disposal.

Have a nice weekend!


Thanks to the great efforts by MS engineers to simplify syntax of DAX! Most beginners are SUCCESSFULLY MISLED to think that they could easily master DAX; but it turns out that the intricacy of the most frequently used RANKX() is still way beyond their comprehension!

DAX is simple, but NOT EASY!

1 ACCEPTED SOLUTION

Hi, @daxer-almighty , thanks for the response and by your hint, I think I found the article unveiling the mechanism under the hood, auto-exist and empty-rows removal. Here's the link to the article: https://www.sqlbi.com/articles/autoexist-and-normalization

"... two different mechanisms are working, ... auto-exist and empty-rows removal.

Auto-exists is a feature working at the server level. Auto-exists makes non-existing combinations of attributes invisible to any client tool that queries your database.

Empty-rows removal is a PivotTable feature that hides rows containing only blank values in the measures."

What I tried is, according to the article, a result of empty-rows removal; whereas auto-exist is a more profound and instrinsic mechanism easily to neglect. Thus I amend another matrix in this regard in my dummy file.


Thanks to the great efforts by MS engineers to simplify syntax of DAX! Most beginners are SUCCESSFULLY MISLED to think that they could easily master DAX; but it turns out that the intricacy of the most frequently used RANKX() is still way beyond their comprehension!

DAX is simple, but NOT EASY!

View solution in original post

2 REPLIES 2
daxer-almighty
Solution Sage
Solution Sage

Visuals always use SUMMARIZECOLUMNS behind the scenes, so it means only those combinations that exist in the fact table are displayed in the matrix.

Hi, @daxer-almighty , thanks for the response and by your hint, I think I found the article unveiling the mechanism under the hood, auto-exist and empty-rows removal. Here's the link to the article: https://www.sqlbi.com/articles/autoexist-and-normalization

"... two different mechanisms are working, ... auto-exist and empty-rows removal.

Auto-exists is a feature working at the server level. Auto-exists makes non-existing combinations of attributes invisible to any client tool that queries your database.

Empty-rows removal is a PivotTable feature that hides rows containing only blank values in the measures."

What I tried is, according to the article, a result of empty-rows removal; whereas auto-exist is a more profound and instrinsic mechanism easily to neglect. Thus I amend another matrix in this regard in my dummy file.


Thanks to the great efforts by MS engineers to simplify syntax of DAX! Most beginners are SUCCESSFULLY MISLED to think that they could easily master DAX; but it turns out that the intricacy of the most frequently used RANKX() is still way beyond their comprehension!

DAX is simple, but NOT EASY!

Helpful resources

Announcements
OCT PBI Update Carousel

Power BI Monthly Update - October 2024

Check out the October 2024 Power BI update to learn about new features.

September Hackathon Carousel

Microsoft Fabric & AI Learning Hackathon

Learn from experts, get hands-on experience, and win awesome prizes.

October NL Carousel

Fabric Community Update - October 2024

Find out what's new and trending in the Fabric Community.