What to do with questions about unpivot / flattening data using Google Sheets?

Question

We have several questions about passing data from a double entry table to a simple table shape.

By double entry table I'm referring to something like this

Item	January	February	March
Chair	20	15	18
Vase	7	5	9

By simple table I'm referring to something like this

Item	Month	Qty
Chair	January	20
Chair	February	15
Chair	March	18
Vase	January	7
Vase	February	5
Vase	March	8

• There are 52 posts that have the word flatten, 46 of them has google-sheets
• There are 10 posts that have the word unpivot, 3 of them are questions which 2 of them has unpivot (it hasn't a tag excerpt & wiki), both have google-sheets. The other question has excel-online.

There are other posts about the same "task" that neither unpivot or flatten were included. Below some examples:

• How to combine dynamic columns in Google Sheets while retaining data in other rows?
• Analyse multiple columns per row
• How to convert repeating rows into columns in Google Sheets
• Transpose multiple columns into single column
• How to sum a range columns from another google sheet

I'm wondering if we should make a mini-retag project starting by adding a tag excerpt to unpivot and / or select some questions as canonical.

Comments, thoughts, suggestions or concerns?

Related

• What question should be used (or set) as the canonical question for questions about split/transpose column values?

Answer 1

Regarding the basic case having one column for n row headers, one row for m column headers and n by m values it's very likely that the best will be to have a canonical question. Some questions that belongs to this case, from older to newer:

• Flatten (pivot) table into a three column array on a Google Spreadsheet

  • It has no linked questions yet.

• Turn a table into a list of row/column/value tuples

  • It's linked to 2 questions. None of theme are duplicates.

• Transpose Ranges repeated by row
  It's already linked to 7 questions, but not all them are duplicates.
  Duplicates:

  • Transform a Google Spreadsheet table? Columns by rows. It belongs to other case as it's about having two columns for row headers.
  • Create row for each entry in a table (ideally without script)

• Restructure (flatten) data of Google Sheets table in a new table

  • It has no linked questions yet.

I'm still not sure what existing question should be used as a canonical question. Suggestions?

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Case having two column headers OR two row headers (with no blank / merged cells). Some questions that belong to this case:

• Two rows for column headers, one column for row headers
  • Displaying specific column header for cells, based on the cell value and its row header

Case having tow column headers OR two row headers with blank / merged cells. Some question that belong to this case:

• Transpose multiple columns into single column