>All you have to do is create an index on Empty( < field > ) and then both the Empty and Not Empty will be optimized.
I do not recommend this. Any condition, especially on "not empty()", would return a LOT of records from the index, just to do Rushmore Optimization. Thus, a query would be "Full Rushmore Optimized" by definition, but not fast. My recent FAQ on Rushmore Optimization explains the details of how this works.
Hilmar.
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)