cfspreadsheet
only omits cells that are completely blank: no value or format (such as when you select a cell and use "clear all"). If it is picking up "extra" columns, it is because one or more of the cells in that column have a value or a custom cell format. Meaning they are not really "blank".
If you know the column position, you can use the columns
attribute to only read only the values in that column. For example, to read column C
:
<cfspreadsheet action="read"
src="c:/path/to/file.xls"
columns="3"
headerrow="1"
query="qResult" />
But I am not sure I understand why this is an issue. If you only need one column, simply ignore the other columns in your code. Can you elaborate on why this is causing an issue?