That's a novel, creative idea - I'll save that one for smaller files. Unfortunately, I'm searching a 25-character field (avg = 18 chars) in a 16.25M record file. The new search file is one record per letter in the field and each record has 15 bytes (10 chars + 4 for a key + 1 for delete mark). So 18 * 16.25M = 292.5M letters (records). 292.5M * 15 bytes puts me at 4.4G - so, indeed it will be too large for this particular application.