Create Parent-Child Hierarchy from indentations

Hi, MartinFO 

Based on your descirption, I created data to reproduce your scenario. The pbix file is attached in the end.

Table:

You may try the following transformations in 'Advanced Editor'.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WCklNzsjLTE7MUchNzEtMT81NzStR0lEytjQwM1SK1YlWUlAILkhNzkwDqinJzM9T8C9LLSrLTC0HKbIwNTEBK3JJLc5Mz4PoMzWH6nPOz0tOLSiBKDS1hIoau0B1wpS5uPm6OkIVmUHFwhJzMlMg9hXkJOZBZS2UYmMB", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [#"Activity Name" = _t, #"Activity ID" = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Activity Name", type text}, {"Activity ID", Int64.Type}}),
    #"Added Index" = Table.AddIndexColumn(#"Changed Type", "Index", 0, 1, Int64.Type),
    #"Added Custom" = Table.AddColumn(#"Added Index", "Custom", each let activityname=[Activity Name],activityid=[Activity ID],index=[Index] in
if Text.StartsWith([Activity Name]," ")
then 
Table.Max(Table.SelectRows(#"Added Index",each [Index]<index and not Text.StartsWith([Activity Name]," ")),"Index")[Activity ID]
else null),
    #"Removed Columns" = Table.RemoveColumns(#"Added Custom",{"Index"}),
    Custom1 = Table.TransformColumns(#"Removed Columns",{"Activity Name",each Text.TrimStart(_)})
in
    Custom1

Result:

Best Regards

Allan

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