I was reading a thread on Quora about why SQL Server is chosen by companies, and another on StackOverflow about why Oracle is a good choice. As much as I sometimes joke about the Oracle RDBMS, I think it's a solid platform, and certainly wouldn't resist working with Oracle databases if the opportunity presented itself. I like working with technology and enjoy learning about how different platforms work. However I also know that if I started working with Oracle, I'd be much less efficient, and certainly quite slower, in producing work than with SQL Server.

I'd also probably make a lot of relatively poor decisions about how to run the database instance.

I'm sure I'd get better writing PL/SQL, but that would take time. And in any setting, that also means that I'd be costing my company money while I learned the tricks, best practices, and skills needed to produce a well tuned, efficient Oracle-based application. It's really no different than the way I have seen many highly skilled Oracle developers and DBAs come to work with SQL Server and try to treat SQL Server as if it ran the same way as Oracle (<shudder>cursors</shudder>).

That's why when I hear about companies making a quick switch to a new platform or language, I question the move. Certainly there are domains of problems that Oracle might solve better than SQL Server. There are situations where MongoDB is better than an RDBMS or Java makes more sense than C++, but there should be strong, solid technical reason why it's worth trying something new. Not because a manager wants to save some licensing fees or a developer wants to try something new.

By all means, experiment, but do so in small ways. Try new technologies with limited investments, and if they work, increase the investment. However for large projects, stick to what your staff knows best. Their skills are often the limiting factor in producing well written software, and in almost every situation, their salaries will far outweigh any cost of software that you license.