Conditional Index M Language - Power Query

[DaxBoi]

Hi guys I have a question I would appreciate help with

DATA 

I have a data table in the following format

Heading 1	01/01/21	01/02/21
A	1	2
B	3	4
C	5	6
Heading 2	01/01/21	01/02/21
A	1	2
C	3	4
Heading 3	01/01/21	01/02/21
D	1	2

The aim is to have this data set look like 

Heading 1		01/01/21	01/02/21
Heading 1	A	1	2
Heading 1	B	3	4
Heading 1	C	5	6
Heading 2		01/01/21	01/02/21
Heading 2	A	1	2
Heading 2	C	3	4

Of course the following step is to remove the italic rows and unpivot the date columns.

QUESTION

I require some assistance in transforming the data table from the first example to the second.

I have added an index and conditional column with an if contains text "heading" but can't get much further than this.

My solution would be to add a column with a "1" for heading 1 and a "2" for heading 2 etc. and then using a lookup table later. 

Happy to take any advice

Thanks!

[Jimmy801 · Accepted solution]

Hello @DaxBoi 

are you sure that you need some graphical output like your second table? Meaning that your headers are repeating throughout your data? Or should it look like this?

if yes, here the approach to get this result

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45W8khNTMnMS1cwVNJRMjDUByIjAyMYxwjCidWJVnIECoGEjcA8JyDLGIhNwDxnIMsUiM3APJiJRiSZ6IxiIswMYwJmuCDMiAUA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Column1 = _t, Column2 = _t, Column3 = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Column1", type text}, {"Column2", type text}, {"Column3", type text}}),
    #"Grouped Rows" = Table.Group(#"Changed Type", {"Column1"}, {{"AllRows", each Table.TransformColumnNames(Table.PromoteHeaders(_), (x)=> if Text.StartsWith(x,"Heading") then "Value" else x)}}, GroupKind.Local, (x,y)=> if Text.StartsWith(y[Column1], "Headin") then 1 else 0),
    #"Expanded AllRows" = Table.ExpandTableColumn(#"Grouped Rows", "AllRows", {"Value", "01/01/2021", "01/02/2021"}, {"Value", "01/01/2021", "01/02/2021"})
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

[Vera_33]

Hi @DaxBoi 

If you simply need Table 1 to Table 2, you can use Fill Down, paste the code in Advanced Editor. The Index column is to keep the original order

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45W8khNTMnMS1cwVNJRMjDUByIjAyMYxwjCidWJVnIECoGEjcA8JyDLGIhNwDxnIMsUiM3APJiJRiSZ6IxiIswMYwJmuCDMiAUA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Column1 = _t, Column2 = _t, Column3 = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Column1", type text}, {"Column2", type text}, {"Column3", type text}}),
    #"Added Index" = Table.AddIndexColumn(#"Changed Type", "Index", 0, 1, Int64.Type),
    #"Added Custom" = Table.AddColumn(#"Added Index", "Custom", each if Text.Contains([Column1],"Heading") then [Column1] else null),
    #"Filled Down" = Table.FillDown(#"Added Custom",{"Custom"}),
    #"Added Custom1" = Table.AddColumn(#"Filled Down", "Custom1", each if Text.Contains([Column1],"Heading") then [Column1] else  [Custom]&[Column1])
in
    #"Added Custom1"