Excel power Query: Grouping and transposing - excel

Question

I have this table in SQL which I will constantly have new storedId and newproductID when I will refresh my data table.
StoreID ProductID Quantity
1 A 4
1 B 5
1 B 9
2 B 3
2 C 4
.
.
7 F 2
I want to group my StoreID together and transpose the Product ID with the sums of Quantity like the table bellow.
Each of my store can have between 0 and 30 products. So If i have 30 products, I would like to have 30 columns "productID" and 30 columns "SumQuantity"
StoredId ProductId1 ProductID2 ... SumQuantity1 SumQuantity2 ...
1 A B 4 14
2 B C 3 4
.
.
7 F 2
.
.
How i can do this in Power Query Excel?

Answer 1

Its hard to do this without custom coding.
Basically ..
Group on StoreID and ProductID then combine the Quantity
Group again on StoreID, and then combine rows for ProductID and Quantity with semicolon delimiter
Split out the columns on the delimiter. This requires 4 lines of custom code, since we don't know how many columns we need in advance.
Convert the numerical ones to numbers from text, which was needed format for above steps
Sample:
let Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMlTSUXIEYhOlWB0IzwmITVF4lnCeMxAbGsG5LiCuMZhrBFWL4DnDTTUHstyAGKgxFgA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [StoreID = _t, ProductID = _t, Quantity = _t]),
#"Changed Type" = Table.TransformColumnTypes(Source,{{"Quantity", type number}}),
// group and sum quantities
#"Grouped Rows" = Table.Group(#"Changed Type", {"StoreID", "ProductID"}, {{"Quantity", each List.Sum([Quantity]), type number}}),
// group second time and combine ProductID and Quantity from different rows onto a single row with ; as delimiter
#"Grouped Rows1" = Table.Group(#"Grouped Rows", {"StoreID"}, {{"ProductID", each Text.Combine(List.Transform([ProductID], each Text.From(_)), ";"), type text},{"Quantity", each Text.Combine(List.Transform([Quantity], each Text.From(_)), ";"), type text}}),
//Dynamically split the two delimited columns into any number of columns
DynamicColumnList = List.Transform({1 ..List.Max(Table.AddColumn(#"Grouped Rows1","Custom", each List.Count(Text.PositionOfAny([ProductID],{";"},Occurrence.All)))[Custom])+1}, each "ProductID." & Text.From(_)),
DynamicColumnList2 = List.Transform({1 ..List.Max(Table.AddColumn(#"Grouped Rows1","Custom", each List.Count(Text.PositionOfAny([Quantity],{";"},Occurrence.All)))[Custom])+1}, each "Quantity." & Text.From(_)),
#"Split Column by Delimiter" = Table.SplitColumn( #"Grouped Rows1", "ProductID", Splitter.SplitTextByDelimiter(";", QuoteStyle.Csv), DynamicColumnList),
#"Split Column by Delimiter2" = Table.SplitColumn( #"Split Column by Delimiter" , "Quantity", Splitter.SplitTextByDelimiter(";", QuoteStyle.Csv), DynamicColumnList2),
// convert numerical to numbers
#"ConvertToNumbers" = Table.TransformColumnTypes (#"Split Column by Delimiter2", List.Transform ( List.Difference(Table.ColumnNames(#"Split Column by Delimiter2"),Table.ColumnNames(#"Split Column by Delimiter")),each {_,type number}))
in #"ConvertToNumbers"

Answer 2

I'm not sure why you'd want data in such a terrible format but here's how I'd approach it.
let
Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMlTSUXIEYhOlWB0IzwmITVF4lnCeMxAbGsG5LiCuMZhrBFWL4DnDTTUHstyAGKgxFgA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [StoreID = _t, ProductID = _t, Quantity = _t]),
#"Changed Type" = Table.TransformColumnTypes(Source,{{"StoreID", Int64.Type}, {"ProductID", type text}, {"Quantity", Int64.Type}}),
#"Grouped Rows" = Table.Group(#"Changed Type", {"StoreID", "ProductID"}, {{"SumQuantity", each List.Sum([Quantity]), type nullable number}}),
#"Custom Grouping" = Table.Group(#"Grouped Rows", {"StoreID"},
{
{"Products", each Table.FromRows({[ProductID]},List.Transform({1..List.Count([ProductID])}, each "ProductID" & Number.ToText(_))), type table},
{"Quantities", each Table.FromRows({[SumQuantity]},List.Transform({1..List.Count([SumQuantity])}, each "SumQuantity" & Number.ToText(_))), type table},
{"Count", Table.RowCount, Int64.Type}
}
),
ColumnsToExpand = List.Max(#"Custom Grouping"[Count]),
ProductColumns = List.Transform({1..ColumnsToExpand}, each "ProductID" & Number.ToText(_)),
QuantityColumns = List.Transform({1..ColumnsToExpand}, each "SumQuantity" & Number.ToText(_)),
#"Expanded Products" = Table.ExpandTableColumn(#"Custom Grouping", "Products", ProductColumns, ProductColumns),
#"Expanded Quantities" = Table.ExpandTableColumn(#"Expanded Products", "Quantities", QuantityColumns, QuantityColumns)
in
#"Expanded Quantities"
The first grouping on StoreID and ProductID is the same as #horseyride suggests but I go a different way from there.
The next step is to group by only StoreID and construct the desired table for each store. This step result looks something like this in the editor (the preview on the bottom is what the selected cell contains):
Let's look at how this table is constructed for "Products".
Table.FromRows(
{[ProductID]},
List.Transform(
{1..List.Count([ProductID])},
each "ProductID" & Number.ToText(_)
)
)
This list [ProductID] is the list of IDs associated with the current store. For the cell selected, it's simply {"A","B"}. Since there are two values, the List.Count is 2. So the above simplifies to this:
Table.FromRows(
{{"A", "B"}},
List.Transform(
{1,2},
each "ProductID" & Number.ToText(_)
)
)
After the list transform this is simply
Table.FromRows({{"A", "B"}}, {"ProductID1", "ProductID2"})
which looks like the preview in the screenshot above.
The construction for the quantities data is analogous. After that column is defined, all that is left is to expand both these columns:
Edit:
As #horseyrides points out, the expansion needs to be made dynamic, so I've added a column to the custom grouping to determine the number of columns to expand into. This number is the maximum count of products for one store, which is then used to generate a list of column names.