Hidden Cell message when merging cells

[annschunior]

I'm trying to merge cells in a spread sheet. I select the columns and use the merge cell command. I get a message that asks "Should the contents of the hidden cells be moved into the first cell?" As far as I know, I don't have any hidden cells. Whether I answer yes or no, the result is a column with no content at all. How do I get the cells to merge?

[FJCC]

What that message should say is "Should the content of the cells that are about to be hidden be moved into the first cell?" If you merge cells A1 and B1, then B1 becomes hidden. What exactly is in the cells before you merge them? Upon merging, you should end up with a cell displaying either the content of the top left cell of the merged range, if you answer No to the message, or the concatenated content of all of the merged cells, if you answer Yes.

[annschunior]

It says just what I quoted it as saying, and it produces one large cell with nothing in it. I'm trying to merge two column by selecting them both. Does that make a difference? There's text in both.

[robleyd]

Here is how it works for me:

Select the cells and choose Format | Merge Cells

The result if Yes is selected.

The result if No is selected

Which is as FJCC said: it seems there may be a slight difference in the wording of the notice between differing versions of AOO - but the outcome is the same.

Edit: Just noticed you said "select columns": if you do that, the text will appear at the bottom of the merged cell range, way down at Row 1048576 which is why the cell appears to have nothing in it until you go to the bottom of the sheet.

[FJCC]

In addition to robleyd's helpful pictures, I want to mention that merging two columns will hide millions of cells to produce a single visible cell. I have seen this cause a spreadsheet to respond very slowly. Do you want to merge pairs of cells in the successive rows of neighboring columns or merge two whole columns into a single cell?

[Villeroy]

This is a huge misunderstanding. Merging cells is just a visual effect to make a group of labels appear as one, for instance

14-21 y
M | F

The main label for the age category is in a merged column label visually grouping the 2 separate male/female column labels.
The displayed text "14-21 y" belongs to the left cell above the "M". The right cell above the "F" becomes hidden.

If you are going to merge a range of cells and there is some content in the cells to be hidden, the program asks how to deal with the values of the cells that are going to be hidden. Either the cell values become hidden or they are concatenated with the text of the visible cell. The program will insert a space character between the merged text.
The visula effect of merging for a more pleasant layout is the one and only purpose of merging cells, and the concatenation is just a little side effect.

If you want to concatenate multiple cell values just use the concatenation operator & or the CONCATENATE function.
A1: John
B1: Doe
=A1&B2 --> JohnDoe
=CONCATENATE(A1 ; B1) --> JohnDoe

=A1 & " " & B2 --> John Doe
=CONCATENATE(A1 ; " " ; B1) --> John Doe

These formulas concatenate A2 and B2, A3 and B3 etc. when you copy the formula cells downwards and they concatenate B1 and C1, C1 and D1, D1 and E1 etc. when you copy the cells to the right.