Identify duplicates

[Anonymous]

Hello

I have a table which is a list of rowid, account numbers and dates of births.  I want to identify rowid where there are duplicate account number and date of birth.  For example in the data shown below Account number 9987 has 3 different date of births so that is OK but Account number 9960 has same date of births and needs to be flagged

1-5L26	9987	06/02/1958 00:00:00
1-5L26	9987	01/01/1900 00:00:00
1-5L26	9987	24/03/1956 00:00:00
1-5L1S	9960	04/09/1974
1-5L1S	9960	04/09/1974 00:00:00

thanks in advance

Jo

[Anonymous · Accepted solution]

You can do this in power query:

Groupby Birthdate and Account

with columns for CountRows and All Rows

Expand the all rows

add a conditional column using the countrows:

then just some cleaning up and setting data types: