Which free database (other than SQL Express) has SQL syntax most similar to T-SQL?

Question

I think there is an upgrade/downgrade path between MySQL and DB2 because they are both pretty ANSI standards compliant.

Other than SQL Express, is there a similar pairing of free-"ish"/paid databases for SQL Server?

Another way to state the question-- of the free db engines that exist, which is the least painful to migrate T-SQL to?

Update-- Background: I'm looking for a suitable downgrade path. I wrote an app that I wanted to post to codeplex and then I realized that the likely audience might not have admin rights, wouldn't be able to cope with the administrativia of MS-SQL, etc.

Answer 1

There is a free version of Sybase ASE available; Sybase supports T-SQL.

Answer 2

One of Microsoft's big advantages with Sql Server over other offerings is that they have a complete compatible solution, no matter where you are on the size-spectrum: from simple desktop engines with SQL Server Compact Edition all the way to massive warehouses with SQL Server Enterprise Edition, you can be confident that there's an upgrade path for your data. The idea seems to be that if your data scales beyond what SQL Server Express Edition can handle, you're doing well enough in your business to afford one of the more expensive editions.

This is especially true because once you're into that scale migrating to another database is not trivial and will be expensive in it's own right. Once your system is that large and complex even simple differences between database engines can be a big deal. Fortunately for most of us, Express Edition is pretty capable.

So in most cases the next upgrade path from SQL Server is... SQL Server. If your database is big enough that a free edition won't cut it, it's big enough that we really need to know exactly what your goals are and what you are trying to accomplish to give you a good recommendation on an alternative.