Useful Excel formula when you need to get the value of a column if it exists in another column.
For example, say I need to get the DescriptionA of an IdA and if the Id exists on another list (IdB), copy the descriptionA to the descriptionB.
=IF(COUNTIF($C$2:$C$9,A2)=0,"",VLOOKUP(A2,$C$2:$D$9,2,FALSE))
The quickest way would be a SQL sentence and extract the information straight from the DB tables.. but if all you had was the spreadsheet, this works quite well.
