Eliminate duplicate rows based on Timestamp

[HxH]

Hi all, 

I have a table that among other columns has an ID and a Timestamp which records the moment when that row was created. For some reasons I'm not going to dive into some IDs are duplicated with different timestamps. I would like to remove them in Power Query by saying: if there are multiple rows with the same ID, keep only the one with the minimum Timestamp. The ID column should in the end be the primary key of the table. I would be able to do this in DAX but I'm not capable of doing that in M. 

Thanks for any help.

[stvsurf · Accepted solution]

You can achieve that by doing the following steps:

1. use a "group by" on "id" and select as operation "All Rows", let's assume you call the column "group"
2. Add a custom column with formula: Table.Min([group],"date")
3. Expand the custom column
4. Expand group
5. create a conditional column (show/hide) where you compare the date from the row with the expanded custom column (which is the minimum date per id)
6. filter on show

1.