Assume there are two columns with data repeated in all both columns. One may wan to extract the unique text values from a specific column based on conditions specified by end-user.
Depending upon the version of MS Excel which you are using, there could be two ways to solve this problem
Solution for MS Excel 2010 and higher versions
If you are using the Power Query add-in, then a few simple steps (no formulas at all) can solve this problem. The result will be dynamic and refreshable (just as in a Pivot Table)
Solution for all versions of MS Excel
While this solution works for all versions of MS Excel, it uses an array formula (Ctrl+Shift+Enter). Array formulas, if used extensively in the workbook, adversely effect the system’s performance.
You may refer to my solution in this workbook.