Phil Factor (9/26/2010)
Itzik has written a very fine blog on the subject of the missing functions Window Functions (OVER Clause) – Help Make a Difference. Also worth a look is PostgreSQL's documentation for Window Functions just so you can see what you're missingWindow Functions and Running totals and sums using PostgreSQL 8.4 Windowing functions . This is a cause that is well-worth supporting, so please vote on Connect for the implementation of all these functions. The most important of all is the first one 'Ordering for Aggregates' as this would allow a simple solution to a whole lot of 'running total' SQL problems.
Thanks for the PostgreSQL links - they are indeed interesting and illuminating.
I didn't include a link for the blog since you need to have a paid membership to view it.
I agree with the most important missing function. I would say that IMHO, the next two are the ROWS/RANGE window sub-clauses, and the WINDOW clause. And if I understand all of these correctly, wouldn't you need the ROWS/RANGE into order to do the 'running total'?
Wayne
Microsoft Certified Master: SQL Server 2008
Author - SQL Server T-SQL Recipes