Allocating based on a different table

[JMikes]

Hello,

I am at a total loss on how to approach this problem. I have two tables (bill table & bill payments table) including fields shown below:

Bill Table:

Bill#	Item#	Amount
Bill1	Item1	8
Bill1	Item2	12
Bill1	Item3	18
Bill2	Item1	6
Bill2	Item2	14
Bill3	Item1	20
Bill4	Item1	30

and

Bill Payment Table

Bill Payment #	Bill #	Paid Amount
BillPmnt1	Bill2	20
BillPmnt1	Bill1	19
BillPmnt2	Bill3	10
BillPmnt3	Bill4	30

I need to figure out a way to allocate the paid amount across the items when a partial payment has been made. For example, Bill1 has 3 items costing $8, $12, and $18 for a total of $38. BillPmnt1 includes a $19 payment on Bill1. So, I need the results table to allocate how much was paid at the item level (ex. Item1 Paid Amount = $8 * $19/$38 = $4).

Desired Result

Bill Payment #	Bill #	Item #	Paid Amount
BillPmnt1	Bill2	Item1	6
BillPmnt1	Bill2	Item2	14
BillPmnt1	Bill1	Item1	4
BillPmnt1	Bill1	Item2	6
BillPmnt1	Bill1	Item3	9
BillPmnt2	Bill3	Item1	10
BillPmnt3	Bill4	Item1	30

First, is this even possible in Power Query? If so, how would I approach this? I thought maybe I'd need to first group the Bill table by Bill # to figure out how much was paid, but I don't really know how I'd proceed from there. Any help is greatly appreciated!!

Thanks!

[dufoq3 · Accepted solution]

Hi @JMikes, try this. You have to replace selected code for both tables with your table references:

Result

let
    BillTable = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WcsrMyTFU0lHyLEnNBdEWSrE6qKJGQNrQCEPYGCSMUG2EZIYZhijYDBO4sDGSYiMDuLAJkrAxUDgWAA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [#"Bill#" = _t, #"Item#" = _t, Amount = _t]),
    ChangedTypeBillTable = Table.TransformColumnTypes(BillTable,{{"Amount", Currency.Type}}),
    BillPaymentTable = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WcsrMyQnIzSsxVNIBs42AtJGBUqwOphSINrREkTKCShmDpFB1GUOlTIC0MVAqFgA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [#"Bill Payment #" = _t, #"Bill #" = _t, #"Paid Amount" = _t]),
    ChangedTypeBillPaymentTable = Table.TransformColumnTypes(BillPaymentTable,{{"Paid Amount", Currency.Type}}),
    GroupedRowsBillTable = Table.Group(ChangedTypeBillTable, {"Bill#"}, {{"All", each _, type table}, {"Total Amount", each List.Sum([Amount]), Currency.Type} }),
    ExpandedAll = Table.ExpandTableColumn(GroupedRowsBillTable, "All", {"Item#", "Amount"}, {"Item#", "Amount"}),
    MergedQueryItself = Table.NestedJoin(ChangedTypeBillPaymentTable, {"Bill #"}, ExpandedAll, {"Bill#"}, "Bill Table", JoinKind.LeftOuter),
    RenamedColumns = Table.RenameColumns(MergedQueryItself,{{"Paid Amount", "Paid Amount Bill"}}),
    ExpandedBillTable = Table.ExpandTableColumn(RenamedColumns, "Bill Table", {"Item#", "Amount", "Total Amount"}, {"Item#", "Amount", "Total Amount"}),
    Ad_PaidAmount = Table.AddColumn(ExpandedBillTable, "Paid Amount", each [Amount] * [Paid Amount Bill] / [Total Amount], Currency.Type),
    RemovedOtherColumns = Table.SelectColumns(Ad_PaidAmount,{"Bill Payment #", "Bill #", "Item#", "Paid Amount"})
in
    RemovedOtherColumns

[lbendlin]

I need to figure out a way to allocate the paid amount across the items when a partial payment has been made

While this is possible in Power Query it must be stated very strongly that Power BI is a reporting tool, not a resource allocation tool.  Power BI has no memory and no concept of variables.  You are better off using a specialized tool.

[JMikes]

Thanks, @lbendlin . The results will actually be used in Excel. I looked up the Power Query forum and it brought me here. Can you still help?

[lbendlin]

The results will actually be used in Excel

Then do the computations in Excel too.