How to number each occurrence of a substring in a cell in Power Query?

[DGuzmanG]

Hello,

I'm fairly new to Power Query and have hit a hiccup that's been bothering me all day. I've read multiple threads here and on the Power BI community and none has really cleared my question, and my logic suggests a few different options to achieve what I want, but my lack of experience blocks any solution I attempt.

Context: I'm building a database for product import/export into WooCommerce, eBay and other channels; which takes some inputs by the (non tech savyy) users in Excel and develops several of the required fields. One of those is the image file names for each product.

I have this columns (in a much larger query table):

Image Base Name	ImageQty	ImageIDs
product-name.jpg	3	product-name.jpg product-name.jpg product-name.jpg
other-product.jpg	5	other-product.jpg other-product.jpg...other-product.jpg

And my desired output would be:

ImageBaseName	ImageQty	ImageIDs
product-name.jpg	3	product-name.jpg product-name.jpg product-name.jpg
other-product.jpg	5	other-product-1.jpg other-product-2.jpg...other-product-5.jpg

In fact I don't need the two first columns if I get the ImageIDs like that. The ImageBaseName column is generated from the input product name. The ImageQTY column is direct input by the user. The ImageIDs column I got so far is from using:

= Table.AddColumn(#"previous step", "ImageIDs", each Text.Trim(Text.Repeat ([ImageBaseName]&" ", [ImageQty]))) 

And these are the options I've considered thus far:

Option 1: Text.Combine(Text.Split ImageIDs and (somehow) count and number each item in the list) and concatenate it all back... Which would probably start like this: Text.Combine(Text.Split,,,

Option 2 Using the UI, splitting the ImageIDs by each space and by a high number of columns (as I don't know how many images each product will have, but probably no more than 12) and then assign a number suffix to each of those columns and then putting it all back together, but it feels messy as hell.

Option 3 Probably theres a clean calculated way to generate the numbered image base names based on the number in the second column, and then attach the .jpg at the end of each, but honestly I don't know how.

I'd like it to be on the same table as I am already dealing with different queries...

Any help would be gladly accepted.

[#2]

@DGuzmanG -

Will this work for you?

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WKijKTylNLtHNS8xN1csqSFfSUTJWitWJVsovyUgt0oVKQ2VMlWJjAQ==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [#"Image Base Name" = _t, ImageQty = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Image Base Name", type text}, {"ImageQty", Int64.Type}}),
    #"Added Custom" = Table.AddColumn(#"Changed Type", "Custom", each List.Transform({1 ..Number.From([ImageQty])}, each Number.From(_))),
    #"Expanded Custom" = Table.ExpandListColumn(#"Added Custom", "Custom"),
    #"Added Custom1" = Table.AddColumn(#"Expanded Custom", "Custom.1", each Text.Insert([Image Base Name],Text.PositionOf([Image Base Name],".",Occurrence.Last),"-"&Text.From([Custom]))),
    #"Grouped Rows" = Table.Group(#"Added Custom1", {"Image Base Name", "ImageQty"}, {{"Data", each _, type table [Image Base Name=text, ImageQty=number, Custom=number, Custom.1=text]}}),
    #"Added Custom2" = Table.AddColumn(#"Grouped Rows", "Custom", each Table.Column([Data],"Custom.1")),
    #"Extracted Values" = Table.TransformColumns(#"Added Custom2", {"Custom", each Text.Combine(List.Transform(_, Text.From), " "), type text}),
    #"Removed Columns" = Table.RemoveColumns(#"Extracted Values",{"Data"})
in
    #"Removed Columns"

[#3 · Accepted solution]

@ChrisMendoza 

I'd simplify a bit

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WKijKTylNLtHNS8xN1csqSFfSUTJWitWJVsovyUgt0oVKQ2VMlWJjAQ==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [#"Image Base Name" = _t, ImageQty = _t]),
    AddImageIDs = Table.AddColumn(
        Source,
        "ImageIDs",
        each
            Text.Combine(
                List.Transform(
                    {1..Number.FromText([ImageQty])},
                    (x)=>
                        Text.BeforeDelimiter([Image Base Name],".") &
                        "-" &
                        Text.From(x) &
                        "." &
                        Text.AfterDelimiter([Image Base Name],".")
                ),
                " "
            )
    )
in
    AddImageIDs

[#4]

@Sergei Baklan @ChrisMendoza 

Thanks for your answers guys!!

Like Sergei mentioned, the solution could be simplified and I used a similar solution to what he suggested, which came up on Stack Overflow:

What I did, was to remove the ".jpg" suffix in a previous step where it generated the ImageBaseName, so that it would just output what should be the filename. And it allowed me to generate the names based on the two first columns of my example (no "ImageIDs" required).

It looked like this:

#"ImageIDsFromList" = Table.AddColumn (
   #"PreviousStep", 
   "ImageIDsList", 
   each 
    Text.Combine(
      List.Transform(
         List.Zip(
            {
            List.Repeat(
               {[ImageBaseName]},
               [ImageQTY]),
            List.Transform(
                  {1..[ImageQTY]}, each "-" & Number.ToText(_) & ".jpg"
               )
            }
         )
       , each Text.Combine(_)
      )
      , ", "
     )
   )
IN
ImageIDsFromList