PowerPivot Implicit Data Conversion

A student noticed an interesting behavior while I was teaching my PowerPivot class last week. He noticed that PowerPivot lets you join a text-based column to a numeric column. As it turns out, PowerPivot does an implicit conversion to text when it discovers that you are attempting to join columns of different data types. However, as a best practice, you should convert numeric columns to a numeric data type, such as Whole Number. This will help PowerPivot minimize storage and improve performance.