Counting Values in a Joined Table

[DHB]

Hi all,

could anyone give me an idea how to count rows in a joined table please?

I have a table of people (all unique records) joined to a table of dates (each person/date combination is unique) with a one to many relationship.  In the people table I'd like to create a DAX expression (DATE COUNT) which will count the number of dates for that person in the dates table.

People

PERSON	DATE COUNT
1234_ABC	3
1255_ABC	1
1234_CDE	6
1344_XYZ	2
1499_MMM	0

Dates

PERSON	DATE
1234_ABC	1/01/2020
1234_ABC	2/01/2020
1234_ABC	3/01/2020
1255_ABC	1/01/2020
1234_CDE	1/01/2020
1234_CDE	2/01/2020
1234_CDE	3/01/2020
1234_CDE	4/01/2020
1234_CDE	5/01/2020
1234_CDE	6/01/2020
1344_XYZ	1/01/2020
1344_XYZ	2/01/2020

Thank you in advance for your help.

[DHB]

@Ahmedx thank you so much for your solution.  How could I change it to only count dates that are "VALID" according to another column?

 So if the Dates table now looked like this:

PERSON	DATE	VALID
1234_ABC	1/01/2020	VALID
1234_ABC	2/01/2020	VALID
1234_ABC	3/01/2020	INVALID
1255_ABC	1/01/2020	VALID
1234_CDE	1/01/2020	VALID
1234_CDE	2/01/2020	VALID
1234_CDE	3/01/2020	INVALID
1234_CDE	4/01/2020	INVALID
1234_CDE	5/01/2020	INVALID
1234_CDE	6/01/2020	INVALID
1344_XYZ	1/01/2020	VALID
1344_XYZ	2/01/2020	VALID

And the result should now look like this;

PERSON	DATE COUNT
1234_ABC	2
1255_ABC	1
1234_CDE	2
1344_XYZ	2
1499_MMM	0

[Ashish_Mathur]

Hi,

Write this measure

Measure = calculate(countrows(Dates),Dates[Valid]="Valid")

Hope this helps.

[DHB]

Thank you @Ashish_Mathur that works well.

[Ashish_Mathur]

You are welcome.

[DHB]

Thank you @Ahmedx 

[Ahmedx · Accepted solution]

you need to just use COUNTROWS functions

measure =

COUNTROWS( 'your'table)+0