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

Don't miss out! 2025 Microsoft Fabric Community Conference, March 31 - April 2, Las Vegas, Nevada. Use code MSCUST for a $150 discount. Prices go up February 11th. Register now.

Reply
fetster
Frequent Visitor

Calculate Age based on difference between 2 dates in seperate tables.

Hi. 

 

I have two tables:

Bookings:

Booking ID

Date Booked 

 

Tickets:

BookingID

TicketID

Name of Person

Date Of Birth

 

One booking can consist of many tickets. 

 

 

I am trying to calculate the age of the people in months on the date they have booked. 

 

I tried this calculation on a new column in the Tickets table:

Age = DATEDIFF('bb_api bookings'[selected_date], RELATED('bb_api tickets'[date_of_birth]),MONTH)
 
But I am getting this error : 
A single value for column 'selected_date' in table 'bb_api bookings' cannot be determined. This can happen when a measure formula refers to a column that contains many values without specifying an aggregation such as min, max, count, or sum to get a single result.
 
Any suggestions what i am doing wrong and how to achieve this please? 
1 ACCEPTED SOLUTION
parry2k
Super User
Super User

@fetster try this new column in the Tickets table:

 

Age = DATEDIFF('bb_api tickets'[date_of_birth],RELATED('bb_api bookings'[booked_date]), MONTH)

 

Check my latest blog post Comparing Selected Client With Other Top N Clients | PeryTUS  I would ❤ Kudos if my solution helped. 👉 If you can spend time posting the question, you can also make efforts to give Kudos to whoever helped to solve your problem. It is a token of appreciation!

Visit us at https://perytus.com, your one-stop-shop for Power BI-related projects/training/consultancy.

 



Subscribe to the @PowerBIHowTo YT channel for an upcoming video on List and Record functions in Power Query!!

Learn Power BI and Fabric - subscribe to our YT channel - Click here: @PowerBIHowTo

If my solution proved useful, I'd be delighted to receive Kudos. When you put effort into asking a question, it's equally thoughtful to acknowledge and give Kudos to the individual who helped you solve the problem. It's a small gesture that shows appreciation and encouragement! ❤


Did I answer your question? Mark my post as a solution. Proud to be a Super User! Appreciate your Kudos 🙂
Feel free to email me with any of your BI needs.

View solution in original post

1 REPLY 1
parry2k
Super User
Super User

@fetster try this new column in the Tickets table:

 

Age = DATEDIFF('bb_api tickets'[date_of_birth],RELATED('bb_api bookings'[booked_date]), MONTH)

 

Check my latest blog post Comparing Selected Client With Other Top N Clients | PeryTUS  I would ❤ Kudos if my solution helped. 👉 If you can spend time posting the question, you can also make efforts to give Kudos to whoever helped to solve your problem. It is a token of appreciation!

Visit us at https://perytus.com, your one-stop-shop for Power BI-related projects/training/consultancy.

 



Subscribe to the @PowerBIHowTo YT channel for an upcoming video on List and Record functions in Power Query!!

Learn Power BI and Fabric - subscribe to our YT channel - Click here: @PowerBIHowTo

If my solution proved useful, I'd be delighted to receive Kudos. When you put effort into asking a question, it's equally thoughtful to acknowledge and give Kudos to the individual who helped you solve the problem. It's a small gesture that shows appreciation and encouragement! ❤


Did I answer your question? Mark my post as a solution. Proud to be a Super User! Appreciate your Kudos 🙂
Feel free to email me with any of your BI needs.

Helpful resources

Announcements
Las Vegas 2025

Join us at the Microsoft Fabric Community Conference

March 31 - April 2, 2025, in Las Vegas, Nevada. Use code MSCUST for a $150 discount! Prices go up Feb. 11th.

Jan25PBI_Carousel

Power BI Monthly Update - January 2025

Check out the January 2025 Power BI update to learn about new features in Reporting, Modeling, and Data Connectivity.

Jan NL Carousel

Fabric Community Update - January 2025

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