问题
If I have the following table (shown in the image below), how can I write a grouped query that would concatenate the grouped results?
For this example, I\'d want to group by the LetterColumn and concatenate the NumberColumn
So the desired results would be:
回答1:
If your table is Source, and if NumberColumn has the number type, then this will work:
= Table.Group(Source, {"LetterColumn"}, {{"Column", each Text.Combine(List.Transform(_[NumberColumn], (x) => Number.ToText(x)), ","), type text}})
Table.Group does a group by operation, which creates a table made up of all of the rows with the same value in LetterColumn. _[NumberColumn] gives a list of the values in the NumberColumn column in this new table. The List.Transform part turns the numbers into text values, and Text.Combine joins those numbers together, with a comma separating each value.
If you need the surrounding quotes as well, you can do this:
= Table.Group(Source, {"LetterColumn"}, {{"Column", each """" & Text.Combine(List.Transform(_[NumberColumn], (x) => Number.ToText(x)), ",") & """", type text}})
"""" represents the " character, and & combines two text values.
回答2:
You can use the GUI to do it this way:
Select your LetterColumn and then Transform / GroupBy:
Select Add Column / Custom Column:
Click opposing arrows at top right of new AllData column to Extract Values from new AllData column:
Remove AllData column.
来源：https://stackoverflow.com/questions/44058355/powerquery-how-can-i-concatenate-grouped-values