Tags: TEXTJOIN

Combine unique entries from a range of cells after satisfying a condition

{2 Comments}

Here is a simple three column dataset showing Item ID, Catalogue Name and Catalogue Year

Item ID Catalogue Name Catalogue Year
A Spring 2012
A Spring 2016
A Spring 2017
B Fall 2014
B Fall 2014
B Fall 2016

The second and third last rows are clear duplicate rows. The task is to create a fourth column (titled as All Year) in this dataset with concatenated entries from the Catalogue Year column for each Item ID. So the expected result is:

Item ID Catalogue Name Catalogue Year All Year
A Spring 2012 2012, 2016, 2017
A Spring 2016 2012, 2016, 2017
A Spring 2017 2012, 2016, 2017
B Fall 2014 2014, 2016
B Fall 2014 2014, 2016
B Fall 2016 2014, 2016

Notice that for Item ID B, the result in every cell of the fourth column is 2014, 2016 and not 2014,2014,2016.  So while joining (concatenating in technical MS Excel terminology) entries from the "Catalogues Year" column in the "All Year" column, only unique entries for that Item ID have to be considered.

Excel 2016 has a TEXTJOIN() function which gets use close to the final result but does not take into account the unique entries only (it takes all entries into account all entries).  On using the TEXTJOIN() array formula in a spare column, here is the result i got:

Item ID Catalogue Name Catalogue Year All Year
A Spring 2012 2012, 2016, 2017
A Spring 2016 2012, 2016, 2017
A Spring 2017 2012, 2016, 2017
B Fall 2014 2014, 2014, 2016
B Fall 2014 2014, 2014, 2016
B Fall 2016 2014, 2014, 2016

Notice that for Item ID B, the result is 2014, 2014, 2017 and not 2014, 2017.  So the TEXTJOIN() function does not work.

I have solved this problem using Power Query (Get and Transform in Excel 2016).  You may download my solution workbook from here.

Prepare an invigilation schedule for each teacher by different time periods

{5 Comments}

Imagine a multi column exam invigilation schedule with the following information

  1. S. No.
  2. Name of staff
  3. Designation of staff member
  4. Two columns for each day on which there is an exam - one for Morning and another for Afternoon
  5. A * under each column if that particular staff member has to be an invigilator during that time period
S. No. Name of staff Designation 09/11/2017-Morning 09/11/2017-Afternoon 10/11/2017-Morning 10/11/2017-Afternoon
1 Tom Lecturer * * *
2 Sam Lecturer * *

This dataset stretches into many more columns.  So if the exams last for 15 days, there will be 30 columns.  The objective is to condense the column expanding dataset into a 5 column one - S. No., Name of Staff, Designation, Morning and Evening.  Under the Morning and Evening columns, the different dates have to be separated by commas in that one single cell.  The expected result is:

Name of staff S. No. Designation Morning Afternoon
Tom 1 Lecturer 09/11/2017, 10/11/2017, 11/11/2017, 13/11/2017, 14/11/2017, 16/11/2017, 17/11/2017 10/11/2017, 13/11/2017, 14/11/2017, 15/11/2017, 16/11/2017, 17/11/2017
Sam 2 Lecturer 09/11/2017, 13/11/2017, 15/11/2017, 16/11/2017 09/11/2017

I can think of 3 ways to solve this problem. Here's a brief about each of those methods:

  1. Using Power Query and Excel's functions - Using Power Query, one can first unpivot the data and then use the TEXTJOIN() function.  This would be an array formula.
  2. Using Power Query only - Using Power Query, one can first unpivot the data and then modify the code to concatenate all dates in a single cell for that invigilator.  One can then Pivot the data in Power Query itself
  3. Using Power Query and PowerPivot - Using Power Query, one can first unpivot the data and then use the CONCATENATEX() function of the PowerPivot.

As you can observe, the common thread in all solutions is that one has to first unpivot the dataset.

You may refer to all my 3 solutions in this workbook.