In my pre-conference session at PASS Munich, I had a question related to the complexities of my recommending LEFT-based partitions... To keep us on track I somewhat avoided the discussion simplifying it to - "it's a best practice because of issues related to MERGE and SPLIT" AND (in typical fashion, as you guys often do :), I was later "called" on it in a discussion. This blog entry details the reasons why I feel that LEFT-based partitions make more sense in a "rolling range" scenario.