Categorize data based on 3 columns

[rodfernandez]

Hi,
i need to create a colum that asigne a value based on other 3 columns.

for example, i have this data table

ID	Date	Type
100	01-01-2021	1
100	02-01-2021	2
100	03-01-2021	1
100	05-01-2021	3
101	02-01-2021	1
101	04-01-2021	2
101	03-01-2021	3
102	05-01-2021	1
102	10-01-2021	1
102	11-01-2021	1

I need to create a new column that for each same ID and type it, assign a letter (from "a" to "z") depending on which came first.
The result should be something like this

ID	Date	Type	New Column
100	01-01-2021	1	1.a
100	02-01-2021	2	2.a
100	03-01-2021	1	1.b
100	05-01-2021	3	3.a
101	02-01-2021	1	1.a
101	04-01-2021	2	2.a
101	03-01-2021	3	3.a
102	05-01-2021	1	1.a
102	10-01-2021	1	1.b
102	11-01-2021	1	1.c

Thanks

[Payeras_BI · Accepted solution]

Hi @rodfernandez ,

Find attached the pbix file with my proposal.

EDIT: Re attached again removing some unnecessary steps and adding List.Buffer.

[rodfernandez]

Perfect, Thanks