Need to fetch multiple values from the same table

[dsbuilder]

Hello, I have a problem that I believe it's simple but I haven't been able to do this. 

Imagine a table like this

L1column	L2column	Number_ext
1.1 Rice
1.1 Rice	1.1.1 Blue Rice	FIVE
1.1 Rice	1.1.2 Green Rice
1.2 Potatoes
1.2 Potatoes	1.2.1 Old Potatoes	TWELVE
1.1 Rice	1.1.1 Blue Rice	TEN, ELEVEN
1.1 Rice	1.1.1 Blue Rice

I want to be able to create a new column that concatenates all the Number_ext column on the rows that have only the L1values and not L2values. Something like this:

L1column	L2column	Number_ext	New column
1.1 Rice			FIVE, TEN, ELEVEN
1.1 Rice	1.1.1 Blue Rice	FIVE
1.1 Rice	1.1.2 Green Rice
1.2 Potatoes			TWELVE
1.2 Potatoes	1.2.1 Old Potatoes	TWELVE
1.1 Rice	1.1.1 Blue Rice	TEN, ELEVEN
1.1 Rice	1.1.1 Blue Rice

I've been trying Lookups and filters and new tables but I haven't been able to do this. 

Can someone please help me with this? 

Thank you!

(this is a dummy table - I don't work with vegetables)

[Jimmy801 · Accepted solution]

Hello @dsbuilder 

check out this solution. It uses Table.Group and AddColumn. This will write your requested data in every column, no only in the first 🙂

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMtQzVAjKTE5V0lFSAONYHRRBIBPIccopTYWJuHmGuWJTZaTgXpSamocwDaLGSCEgvySxJD+1GM0KFAkgF2iaf04KsmBIuKsPdrtQXRTi6qej4OrjGubqR1gx0PpYAA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [L1column = _t, L2column = _t, Number_ext = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"L1column", type text}, {"L2column", type text}, {"Number_ext", type text}}),
    #"Grouped Rows" = Table.Group(#"Changed Type", {"L1column"}, {{"AllRows", each _, type table [L1column=text, L2column=text, Number_ext=text]}}),
    #"Added Custom" = Table.AddColumn(#"Grouped Rows", "Conc", each Text.Combine([AllRows][#"Number_ext"])),
    #"Expanded AllRows" = Table.ExpandTableColumn(#"Added Custom", "AllRows", {"L1column", "Number_ext"}, {"L1column.1", "Number_ext"})
in
    #"Expanded AllRows"

Copy paste this code to the advanced editor in a new blank query to see how the solution works.

If this post helps or solves your problem, please mark it as solution (to help other users find useful content and to acknowledge the work of users that helped you)
Kudoes are nice too

Have fun

Jimmy

[dsbuilder]

Thank you @Jimmy801 ! Thanks for your quick reply!