Transform a table in Excel: transpose vs pivot and repeaded cells

[KLolli]

Hello,

I need help with transforming a table: from the example on the left, to the one on the right.

I tried pivot column but where more dates are present for the same name, I had an error.

I added an additional column and then pivot, but ended up with thousands of columns, one for each individual date.

Many thanks for your time and help.

KL

[#2]

@KLolli 

E2: =UNIQUE(A2:A7)
F1: ="DATE "&SEQUENCE(,MAX(COUNTIFS(A2:A7,E2#)))
F2: =TRANSPOSE(FILTER($B$2:$B$7,$A$2:$A$7=E2))

[#3]

Dear Detlef,

Thank you very much for your reply!
I have data in cells F2:XX1000 and I typed the first formula in E2=UNIQUE(F2:XX2) but it gave me a #Spill! error. Will read more to find out what I am doing wrong.

Many thanks,

KL

[#4]

Your screenshot shows only 1 column with letters and not 654 columns.

[#5]

Hi,

Essentially I start from a table like the one on the left, 2 columns, one for names and one for dates and I want a "result table" like the one on the left.
I managed to get a table that has many rows (one for each date in column B) using Power query-pivot colunm and I applied your Unique formula to that (now will try on the original table). I managed to get it work, and it does the job, now my problem is that I don't know how to automate this.
I need tables in order to be able to update automatically the data every time I receave a new extract, that's why I was hoping there was a solution via Power query.

[#6]

@KLolli 

(one way) Power Query / M code:

let
    Source = Excel.CurrentWorkbook(){[Name="Table1"]}[Content],
    ChangedTypes = Table.TransformColumnTypes(Source,
        {{"Alpha", type text}, {"Date", type date}}
    ),
    GroupedRows = Table.Group(ChangedTypes, {"Alpha"},
        {"DATA", each
            Table.Transpose(
                Table.SelectColumns(_, {"Date"})
            ), type table
        }
    ),
    ColumnNames = List.TransformMany({"Column", "DATE "},
        each {1..List.Max(List.Transform(GroupedRows[DATA], Table.ColumnCount))},
        (x, y)=> x & Text.From(y)
    ),
    SplittedList = List.Split(ColumnNames, List.Count(ColumnNames)/2),
    ExpandedData = Table.ExpandTableColumn(GroupedRows, "DATA",
        List.First(SplittedList)
    ),
    RenamedColumns = Table.RenameColumns(ExpandedData,
        List.Zip(
            { List.First(SplittedList), List.Last(SplittedList) }
        )
    ),
    TypedDate = Table.TransformColumnTypes(RenamedColumns,
        List.Transform(List.Last(SplittedList), each {_, type date})
    )
in
    TypedDate

Sample avail. here

[#7 · Accepted solution]

@KLolli 

On reflection the following is more straightforward and less complex to understand + Columns names are fully dynamic: whatever the names of your 2 columns are in the source table this will work as long as the column containing the dates is the 2nd column

let
    Source = Excel.CurrentWorkbook(){[Name="Table1"]}[Content],
    SourceColumns = Table.ColumnNames(Source),
    FirstColumn = List.First(SourceColumns),
    GroupedRows = Table.Group(Source, FirstColumn,
        {"DATA", each Table.FromRows(
                { {Table.FirstValue(_)} & Table.Column(_, List.Last(SourceColumns)) }
            ), type table
        }
    ),
    CombinedTables = Table.Combine(GroupedRows[DATA]),
    DateColumns = List.Transform({1..Table.ColumnCount(CombinedTables)-1}, each
        "DATE " & Text.From(_)
    ),
    RenamedColumns = Table.RenameColumns(CombinedTables,
        List.Zip({
            Table.ColumnNames(CombinedTables),
            {FirstColumn} & DateColumns
        })
    ),
    TypedDate = Table.TransformColumnTypes(RenamedColumns,
        List.Transform(DateColumns, each {_, type date})
    )
in
    TypedDate

Sample updated - see BetterQuery

[#8]

Dear L z.,

Thank you so much for the time you spent to solve my problem.
I am not an expert and I will try to figure out how to apply your solution, and I'll let you know if I'll manage to do that, but in the meantime, I just want to thank you again!

KL

[#9]

Dear L z.,

Thank you so so much! I manage to use it and it work perfectly with my data set.
Now will try to learn better what each step is/mean.
Once more, thank you! Fantastic!
KL

[#10]

@KLolli Glad I could help & Thanks for posting back. Just in case PQ doc is here