How do I improve my use of this?

If there are two data sets and you want to see if any data from one set exists in another set then use this.

If you have two sets of data, highlight the second set and in the top left corner of the screen is the name box, in this box type 'Range1' and press the Enter key. Create a new column in your first set of data. In the first cell use the following formula:

=VLOOKUP(B1,Range1,1,FALSE)

This is essentially saying "take the value in B1 (B is the ID column of your first data set), and see if it occurs anywhere in Range1 (Range1 is the ID column of your second data set). If it does appear then it will return the ID (column 1, hence the 1 in the formula) and if it doesn't appear then it will return '#N/A'. The value of 1 will make it return the ID value. You can return any column in the range. For example, if you have column1 as the ID and column2 as the full name then you can change the formula as follows to return the second colum and therefore show the name:

=VLOOKUP(B1,Range1,2,FALSE)

Please see attached example

Attached files...

Vlookup-example.xls