Stack columns with Power Query

Question

I am trying to stack three columns like below on Power BI. My example dataset is following:

Processo	Finalidade 1	Finalidade 2	Finalidade 3
1	Maçã	Banana	Mamão
2	Banana
3	Mamão	Banana

However, I would like that it stay like this:

Processo	Finalidade
1	Maçã
2	Banana
3	Mamão
1	Banana
2
3	Banana
1	Mamão
2
3

I tried to transpose columns but I can't this result.

Answer 1

Based on your input data and the hint in the comments I did it like that

let
    Source = Excel.CurrentWorkbook(){[Name="tblData"]}[Content],
    Step1 = Table.TransformColumnTypes(Source,{{"Processo", Int64.Type}, {"Finalidade 1", type text}, {"Finalidade 2", type text}, {"Finalidade 3", type text}}),
    tblUnPivot = Table.ReplaceValue(Step1,null,"",Replacer.ReplaceValue,{"Finalidade 2"}),
    replaceValues = Table.ReplaceValue(tblUnPivot,null,"",Replacer.ReplaceValue,{"Finalidade 3"}),
    unpivot = Table.UnpivotOtherColumns(replaceValues, {"Processo"}, "Attribut", "Wert"),
    sorted = Table.Sort(unpivot,{{"Attribut", Order.Ascending}, {"Processo", Order.Ascending}}),
    removeCol = Table.RemoveColumns(sorted,{"Attribut"}),
    renameCol = Table.RenameColumns(removeCol,{{"Wert", "Finalidade"}})
in
    renameCol

Result looks like

But the solution strongly depends on the naming of the columns Finalidade 1 etc.

PS Another solution which is independet of the naming of the columns could look like that

let
    Source = Excel.CurrentWorkbook(){[Name="tblData"]}[Content],
    Step1 = Table.TransformColumnTypes(Source,{{"Processo", Int64.Type}, {"Finalidade 1", type text}, {"Finalidade 2", type text}, {"Finalidade 3", type text}}),
    tblUnPivot = Table.ReplaceValue(Step1,null,"",Replacer.ReplaceValue,{"Finalidade 2"}),
    replaceValues = Table.ReplaceValue(tblUnPivot,null,"",Replacer.ReplaceValue,{"Finalidade 3"}),
    unpivot = Table.UnpivotOtherColumns(replaceValues, {"Processo"}, "Attribut", "Wert"),
    addColumn = Table.AddColumn(unpivot, "colPos", each List.PositionOf(Table.ColumnNames(Step1),[Attribut])),
    #"Neu angeordnete Spalten" = Table.ReorderColumns(addColumn,{"Processo", "colPos", "Attribut", "Wert"}),
    removeCol1 = Table.RemoveColumns(#"Neu angeordnete Spalten",{"Attribut"}),
    sortRows = Table.Sort(removeCol1,{{"colPos", Order.Ascending}, {"Processo", Order.Ascending}}),
    renameCol = Table.RenameColumns(sortRows,{{"Wert", "Fianlidade"}}),
    removeCol2 = Table.RemoveColumns(renameCol,{"colPos"})
in
    removeCol2