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

Join us at FabCon Atlanta from March 16 - 20, 2026, for the ultimate Fabric, Power BI, AI and SQL community-led event. Save $200 with code FABCOMM. Register now.

Reply
Anonymous
Not applicable

Calculate Datediff between two tables with Many to Many Relationship

Hello,

I am trying to calculate the number of hours betwee two dates in two tables with a many to many relationship. The relationship between the tables is based on encounter id. Table 1 contains activation events and Table 2 contains drug administrations for each encounter. I need to determine whether there were 24 hours between the activation time in Table 1 and a related administration time in Table 2 for encounters. I can't figure out how to approach this problem.

 

Any help is sincerely appreciated.

 

Thank you.

1 REPLY 1
Greg_Deckler
Community Champion
Community Champion

@Anonymous 

First thing, you should eliminate your many-to-many if at all possible. You can do this by creating a bridge table of distinct values between the two tables or you can create a combination key using concatenation of 2 or more columns.


Also, please see this post regarding How to Get Your Question Answered Quickly: https://community.powerbi.com/t5/Community-Blog/How-to-Get-Your-Question-Answered-Quickly/ba-p/38490

The most important parts are:
1. Sample data as text, use the table tool in the editing bar
2. Expected output from sample data
3. Explanation in words of how to get from 1. to 2.



Follow on LinkedIn
@ me in replies or I'll lose your thread!!!
Instead of a Kudo, please vote for this idea
Become an expert!: Enterprise DNA
External Tools: MSHGQM
YouTube Channel!: Microsoft Hates Greg
Latest book!:
DAX For Humans

DAX is easy, CALCULATE makes DAX hard...

Helpful resources

Announcements
FabCon Global Hackathon Carousel

FabCon Global Hackathon

Join the Fabric FabCon Global Hackathon—running virtually through Nov 3. Open to all skill levels. $10,000 in prizes!

October Power BI Update Carousel

Power BI Monthly Update - October 2025

Check out the October 2025 Power BI update to learn about new features.

FabCon Atlanta 2026 carousel

FabCon Atlanta 2026

Join us at FabCon Atlanta, March 16-20, for the ultimate Fabric, Power BI, AI and SQL community-led event. Save $200 with code FABCOMM.