Forum Discussion
Sub aggregation between records
An "Artist Impression" in this video (explaining the code below) how it could look like in Power Query with the data from an Excel file.
let Source = Excel.Workbook(File.Contents("C:\Users\Marcel\Documents\Forum bijdragen\Power BI Community\Subaggregation between values.xlsx"), null, true), Tabel1_Table = Source{[Item="Tabel1",Kind="Table"]}[Data], #"Changed Type" = Table.TransformColumnTypes(Tabel1_Table,{{"Timestamp", type datetime}, {"Wood", Int64.Type}, {"Fuel", Int64.Type}}), #"Added Index" = Table.AddIndexColumn(#"Changed Type", "Index", 0, 1), #"Added Custom" = Table.AddColumn(#"Added Index", "StartIndex", each if [Wood] = null then [Index] else null, Int64.Type), #"Filled Up" = Table.FillUp(#"Added Custom",{"StartIndex"}), #"Added Custom1" = Table.AddColumn(#"Filled Up", "EndIndex+1", each if [Wood] <> null then [Index] else null), #"Filled Up1" = Table.FillUp(#"Added Custom1",{"EndIndex+1"}), #"Added Index1" = Table.AddIndexColumn(#"Filled Up1", "Index.1", 1, 1), #"Merged Queries" = Table.NestedJoin(#"Added Index1",{"Index.1"},#"Added Index1",{"Index"},"NewColumn",JoinKind.LeftOuter), #"Removed Columns" = Table.RemoveColumns(#"Merged Queries",{"Index", "EndIndex+1", "Index.1"}), #"Expanded NewColumn" = Table.ExpandTableColumn(#"Removed Columns", "NewColumn", {"EndIndex+1"}, {"EndIndex+1"}), #"Inserted Subtraction" = Table.AddColumn(#"Expanded NewColumn", "Count", each [#"EndIndex+1"] - [StartIndex], type number), #"Added Custom2" = Table.AddColumn(#"Inserted Subtraction", "TotalFuel", each if [Wood] <> null and [StartIndex] <> null then List.Sum(List.Range(#"Removed Columns"[Fuel],[StartIndex],[Count])) else null), #"Removed Columns1" = Table.RemoveColumns(#"Added Custom2",{"StartIndex", "EndIndex+1", "Count"}) in #"Removed Columns1"
Wow Phil_Seamark, that's some code to learn from :-)
Actually in the query-editor, it would be pretty easy to create an additional column with the desired Timestamp, one can then simply aggregate on it:
1) Add a column with a forumla like this: if [Wood] <> null then [Timestamp] else null
2) Check this new column, rightclick your mouse and Fill-down the values. This will allocate the Timestamp "from above" to all the following rows until the next row with an entry in "Wood".
If the blanks in the wood-column are not null, you might need to adjust your formula like this:
if [Wood] <> "" then [Timestamp] else null
ImkeF Just because something can be done in DAX doesn't mean it should be. I'd say my approach (if correct) wouldn't be memory efficient and If it was something I was working on I would definitely push the transform upstream to Power Query or further if poss.
An "Artist Impression" in this video (explaining the code below) how it could look like in Power Query with the data from an Excel file.
let Source = Excel.Workbook(File.Contents("C:\Users\Marcel\Documents\Forum bijdragen\Power BI Community\Subaggregation between values.xlsx"), null, true), Tabel1_Table = Source{[Item="Tabel1",Kind="Table"]}[Data], #"Changed Type" = Table.TransformColumnTypes(Tabel1_Table,{{"Timestamp", type datetime}, {"Wood", Int64.Type}, {"Fuel", Int64.Type}}), #"Added Index" = Table.AddIndexColumn(#"Changed Type", "Index", 0, 1), #"Added Custom" = Table.AddColumn(#"Added Index", "StartIndex", each if [Wood] = null then [Index] else null, Int64.Type), #"Filled Up" = Table.FillUp(#"Added Custom",{"StartIndex"}), #"Added Custom1" = Table.AddColumn(#"Filled Up", "EndIndex+1", each if [Wood] <> null then [Index] else null), #"Filled Up1" = Table.FillUp(#"Added Custom1",{"EndIndex+1"}), #"Added Index1" = Table.AddIndexColumn(#"Filled Up1", "Index.1", 1, 1), #"Merged Queries" = Table.NestedJoin(#"Added Index1",{"Index.1"},#"Added Index1",{"Index"},"NewColumn",JoinKind.LeftOuter), #"Removed Columns" = Table.RemoveColumns(#"Merged Queries",{"Index", "EndIndex+1", "Index.1"}), #"Expanded NewColumn" = Table.ExpandTableColumn(#"Removed Columns", "NewColumn", {"EndIndex+1"}, {"EndIndex+1"}), #"Inserted Subtraction" = Table.AddColumn(#"Expanded NewColumn", "Count", each [#"EndIndex+1"] - [StartIndex], type number), #"Added Custom2" = Table.AddColumn(#"Inserted Subtraction", "TotalFuel", each if [Wood] <> null and [StartIndex] <> null then List.Sum(List.Range(#"Removed Columns"[Fuel],[StartIndex],[Count])) else null), #"Removed Columns1" = Table.RemoveColumns(#"Added Custom2",{"StartIndex", "EndIndex+1", "Count"}) in #"Removed Columns1"