In data-driven web-based systems the database tier should provide fast access to data, transaction processing, and maintain data integrity. Even dealing with data access security, as was important in client/server projects in the past, is not that important in web-based development anymore, because data access usulay happens in the context of the same account. If we add more features into the database, such as managing objects, inheritance, files, sending email, reading emails, etc. - we would just be taking the job from the middle-tier or from other systems, and overload the database with features that is not really a job of the database. Well, Micosoft did not bad job by integrating some "other features" into the SQLServer without sacrificing the main features of the database which I listed at the beginning of this post (alsthough, the MS SQLMail, MS DTS and other sub systems still need improvements). However, other vendors tried to differentiate themselves on the maket by adding OOP and other features, and as a result sacrificed for example performance. So, I guess the main question in your case would be what do you expect from the database system - the main data-related features or additional features that sound cool and nice.