Merge values in multiple columns into one - vba

Question

I have the following data structure:
As you see in column J, I am trying to merge data into one column from columns A & C & E & G.
I am using this formula:
=IF(ROW()<=COUNTA($A:$A);INDEX($A:$C;ROW();COLUMN(A1));INDEX($A:$C;ROW()-COUNTA($A:$A)+1;COLUMN(C1)))
and I get the values in column K as you see. Currently this formula is merging only two columns. How to modify it to merge all four columns?
And how to only get those values starting from row 5?
The column height will vary constantly: sometimes there are 10 values in column A and sometimes there are 2 values.
Either any excel formula or any VBA code will be acceptable.

Answer 1

There is a fairly standard method for retrieving unique values from a column but not multiple columns. To achieve the retrieval from multiple columns you need to stack multiple formulas together with the processing being passed to successive columns one the earlier formula errors out.
      
The array formula¹ in J5 is,
=IFERROR(INDEX($A$5:$A$99, MATCH(0, IF(LEN($A$5:$A$99), COUNTIF(J$4:J4, $A$5:$A$99), 1), 0)),
IFERROR(INDEX($C$5:$C$99, MATCH(0, IF(LEN($C$5:$C$99), COUNTIF(J$4:J4, $C$5:$C$99), 1), 0)),
IFERROR(INDEX($E$5:$E$99, MATCH(0, IF(LEN($E$5:$E$99), COUNTIF(J$4:J4, $E$5:$E$99), 1), 0)),
IFERROR(INDEX($G$5:$G$99, MATCH(0, IF(LEN($G$5:$G$99), COUNTIF(J$4:J4, $G$5:$G$99), 1), 0)),
""))))
I have only included columns A, C, E and G as your sample data shows only duplicates in columns B, D, F, and H.
¹ Array formulas need to be finalized with Ctrl+Shift+Enter↵. If entered correctly, Excel with wrap the formula in braces (e.g. { and }). You do not type the braces in yourself. Once entered into the first cell correctly, they can be filled or copied down or right just like any other formula. Try and reduce your full-column references to ranges more closely representing the extents of your actual data. Array formulas chew up calculation cycles logarithmically so it is good practise to narrow the referenced ranges to a minimum. See Guidelines and examples of array formulas for more information.

Answer 2

This answer is another way of thinking about the formulas you could use for this sort of task. It gets to the point made by #Jeeped that it is difficult to find unique values in multiple columns. My first step then is to create a single column.
If you can live with a helper column, these formulas might be a tad easier to maintain than the nested IFERROR already proposed. They are equally difficult to understand though at first glance. The other upside is that it scales nicely if the number of columns involved increases.
It is possible using CHOOSE and some INDEX math to build a single column array of a group of separated columns. The trick is that CHOOSE will join discontinuous ranges side-by-side when given an array as the selecting parameter. If this starts with columns of the same size, you can then use division and mod math to turn it into a single column.
Picture of ranges shows the four groups of data with duplicates colored red.
Formula in F2:F31 is an array formula. This is combining all of the columns into an array and then back into a single column. I selected the columns out of order just to emphasize that it is handling a discontinuous range.
=INDEX(CHOOSE({1,2,3,4}, A2:A7,C2:C7,B2:B7,D2:D7), MOD(ROW(1:30)-1, ROWS(A2:A7))+1,INT((ROW(1:30)-1)/ROWS(A2:A7))+1)
The array formula in H2 and copied down is then the standard formula for unique values. The one exception is that instead of avoiding blanks like normal, I am avoiding 0 values.
=IFERROR(INDEX(F2:F31,MATCH(0,IF(F2:F31=0,1,COUNTIF($H$1:H1,F2:F31)),0)),"")
A couple of other comments about this approach:
In the CHOOSE, I am using {1,2,3,4}. This could be replaced with TRANSPOSE(ROWS(1:4)) or whatever number of columns you have.
There is also a ROWS(A2:A7) in 2 places, this could just be 2:7 or 1:6 or whatever size was used for the column size. I used one of the data ranges so that the coloring was simplified and to emphasize it needs to match the size of the block.
And the ROW(1:30) is used for the number of total items to collect. It really only needs to be 1:24 since there are 6*4 items, but I made it big while testing.
There are definitely a couple of downsides to this approach, but it may be a good trick to keep in the toolbox. Never know when you might want to make a column out of discontinuous ranges. The largest downside is that the columns of data all need to be the same size (and of course the helper column).

Answer 3

This code will do what you ask:
Sub MoveData()
START_ROW = 5
START_COL = 1
STEP_COL = 2
OUTPUT_ROW = 5
OUTPUT_COL = 10
Row = START_ROW
Col = START_COL
Out_Row = OUTPUT_ROW
While Col < OUTPUT_COL
While Cells(Row, Col).Value <> ""
Cells(Out_Row, OUTPUT_COL).Value = Cells(Row, Col).Value
Out_Row = Out_Row + 1
Row = Row + 1
Wend
Row = START_ROW
Col = Col + STEP_COL
Wend
End Sub

Answer 4

Think you guys are making this complicated. Just pull the range of data into power query , select all the columns and unpivot them this will bring all the data into a single column