I'm a new member to these forums, looking for some impartial expert advice about selecting a database vendor, and hoping I can find that here. This is the best forum I could figure for this request, but if there's a more appropriate one, please feel free to move the thread. I did cross-post to a couple of other database forum sites as well, so apologies in advance if you see a duplicate post.

Our situation is this: We're a company that specializes in providing Web-based consumer sales for our clients. We're currently using Sybase ASA 9, running several different instances simultaneously (typically one per client; we intend to continue that practice).

We're looking at changing databases because of:
  • the age of ASA 9,
  • the lack of real-time replication/clustering in ASA 9,
  • the performance of ASA 9 under stress has not been very good,
  • the fact that ASA isn't really intended for large-scale enterprise operations, and
  • our new hosting provider won't administer Sybase databases.

The leading candidates we're looking at are MySQL & SQL Server. Upgrading to Sybase ASA 11 is something of an option, but not a preferred one because of some of the reasons listed above. Oracle's license costs are beyond our budget, and the schema/functionality differences are likely more than we'd like to tackle.

What recommendations would you folks make between the two(/three)? Our primary decision-making criteria are:
  • Ease of migration from ASA 9 schema
  • Ease of data schema updates
  • Basic SELECT/INSERT/UPDATE performance
  • Replication/clustering support (especially from a performance standpoint)
  • Tools / Ease of administration
  • Ongoing cost of maintenance
  • Availability of technical resources (online information, personnel, consultants, etc.)
  • Day-to-day pros/cons of each platform

We'll be performing our own internal assessment of each database wrt these criteria as well, but unfortunately we likely won't have the time & resources to do a full port to each database prior to having to make a decision. So any insight & advice about the choice we should make, or things we should know, would be greatly appreciated. Thank you very much.