I\'m not fanatic on any database but I wish to see differences between vendors.
For instance, I use mostly Oracle and I see that others (MySQL, SQL Server, PostgreSQL, .
Both SQL Server and MySQL don't support the standard "double pipe" for string concatenation, while every other DB seems to. (Update: apparently MySQL does... see below)
But this could be fixed... in the code for MySQL, and via http://connect.microsoft.com/SQLServer/feedback/ViewFeedback.aspx?FeedbackID=259291 for SQL Server.