Flow Chart - structuring data

[destank]

Hi all,

I would like to present actions by user in Sankey flow chart custom visual. This visual requires two columns: Source and Destination.

If we consider following dataset that has USER ID, timestamp and Action columns:

User ID	timestamp	Action
1	14/05/2020 01:55:46	Select
1	14/05/2020 01:56:03	Delete
2	14/05/2020 01:56:03	Select
3	13/05/2020 23:12:45	Select
3	13/05/2020 23:12:51	Update
3	14/05/2020 23:12:55	Select

I need to manipulate this dataset to looks like this:

User ID	source	destination
1	select	delete
2	select
3	select	update
3	update	select

I tried with creating custom column using DAX but this way it runs out of memory due to a large dataset:

Destination =
var _cDate =Table[timestamp]

var _calc = CALCULATE(MIN(Table[Action]),FILTER(ALLEXCEPT(Table,Table[User ID]),Table[timestamp]>_cDate))

return _calc

Is there a way I can manipulate initial dataset in Power Query to get desired output?

Thanks in advance

[v-xicai · Accepted solution]

Hi @destank ,

You may add Index column( From 0 ), then add another Index column(From 1), merge this table with original current table , setting more like below.

Let

    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMlTSUTIw1Tc00TcyMDJQMDC0MjW1MjEDigan5qQmlyjF6mBVZGZlYAwUdQEqKkkFKzLCqQjJJGOoImOIIiNjK0MjKxNTIhSZghwRWpCSCLXOGNU6LCbFAgA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [#"User ID" = _t, timestamp = _t, Action = _t]),

    #"Changed Type" = Table.TransformColumnTypes(Source,{{"User ID", Int64.Type}, {"timestamp", type datetime}, {"Action", type text}}),

    #"Added Index" = Table.AddIndexColumn(#"Changed Type", "Index", 0, 1, Int64.Type),

    #"Added Index1" = Table.AddIndexColumn(#"Added Index", "Index.1", 1, 1, Int64.Type),

    #"Merged Queries" = Table.NestedJoin(#"Added Index1", {"User ID", "Index.1"}, #"Added Index1", {"User ID", "Index"}, "Added Index1", JoinKind.LeftOuter),

    #"Expanded Added Index1" = Table.ExpandTableColumn(#"Merged Queries", "Added Index1", {"Action"}, {"Added Index1.Action"}),

    #"Sorted Rows" = Table.Sort(#"Expanded Added Index1",{{"User ID", Order.Ascending}}),

    #"Removed Columns" = Table.RemoveColumns(#"Sorted Rows",{"Index", "Index.1"}),

    #"Renamed Columns" = Table.RenameColumns(#"Removed Columns",{{"Action", "Source"}, {"Added Index1.Action", "destination"}})

in

    #"Renamed Columns"

You can download the pbix form here.

Best Regards,

Amy 

Community Support Team _ Amy

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

[destank]

Thanks Amy!