If value is true return first entry found from another table

[Schwurblini]

Dear Community

I have an issue with a query and i could need some help:

I have a table (Table A) with merchants that have registered on a specific date. These merchants have a unique ID and a Creation date.

Now i have a second table (Table B) where i track the transactions of these Merchants with the unique ID.

I need a query where i can compare the date when they were created and when they did their first transaction. I would imagine in  something like a new column in Table A which checks in Table B if the Unique ID is there and then returns the first "Date" entry it found)

Table A:

 

Table B:

 

As you can see in Table B "978193" is in there twice because he did a transaction in week 1 and 2. Now i would need to know, fro Table A when he was created and when he did his first transaction.

If he was created and never did any transaction, the return value would be "No transactions done"

Can yo help me with that?

Thank you so much and best regards

[mickey64 · Accepted solution]

For your reference.

Step 0: I use these data tables.

Table A:

Topnode Number VP Create date
955758 08/01/2021
960651 21/01/2021
962197 26/01/2021
963128 27/01/2021
964017 30/01/2021
964497 02/02/2021
964743 02/02/2021
965216 03/02/2021
965605 04/02/2021
969300 15/02/2021
969578 16/02/2021
970595 18/02/2021
978193 23/03/2021
980164 07/05/2021
1143077 12/08/2021
1111255 30/09/2021
1129074 13/10/2021

Table B:

Month Week All Topnodes
1.2022 1.2022 970595
1.2022 1.2002 978193
1.2022 2.2002 978193
1.2022 2.2002 980164
1.2022 2.2002 1143077
1.2022 3.2022 978193
1.2022 3.2022 1111255
1.2022 3.2022 1129074
1.2022 4.2002 970595
1.2022 4.2002 978193
1.2022 4.2002 980164

Step 1: I add a relationship.

Step 2: I make a measure.

    Min Week = MIN('Table B'[Week])

Step 3: I make a matrix.

[Schwurblini]

Thats great, i forgot to mention that i already had a relationship, so i couldnt connect them this way but i circumvented this with a "SUMMARIZE" Table and linked it like you mentioned. Worked like a charm

Best of thanks