Solomon Rutzky (5/5/2010)
...the WHILE loop shouldn't be the best performing option, but sadly it is.
Are you sure Solomon? I would expect the APPLY + $PARTITION approach to be faster (see code posted earlier) as well as being more flexible (it dynamically accounts for extra/fewer partitions) and set-based.
Paul White
SQLPerformance.com
SQLkiwi blog
@SQL_Kiwi