I just found my first fundamental difference between execution plans in SQL Server 2005 and SQL Server 2008. In 2005 when you run an query and have it display an XML execution plan by issuing the statement “SET STATISTICS XML ON” you get a second result set that includes a URL. The same thing happens in 2008. When you click on that URL in 2005 it opens the XML file in a new window. If you want to look at the graphical plan, you have to save the file with a “*.SQLPLAN” exentension. In 2008 if you click on the URL, it opens a new window, but it shows the graphical plan. What happened to the XML? The developers at Microsoft are smart, that’s what happened. If you then right click on that graphical plan a menu choice “Show Execution Plan XML…” is available. Clicking on that opens the XML plan.
So I went one step further. I knew that the graphical plan in 2005 was just an XML plan, if not so readily accessible (do a “Save As” and force an XML extension on it). So I right clicked on a graphical plan that I generated the old fashioned way. Sure enough, the same menu choice to show the XML was there. Nice functionality.