I've seen a surprising amount of companies with a stack of Java/Linux for the application and SQL Server/Windows for the database. Just look at Indeed.com's job posting if you don't believe me[1]. If SQL Server was on Linux, they'd switch in a minute.
RDBMSes that you pay for are still able to out perform free, community-developed systems [2]. I've done work on both the DBA and the developer side on Postgres, MySQL, and SQL Server, and I can tell you that if platform and cost were never an issue, I'd choose the latter every time.
I've been involved in several projects with SQL Server on Windows and Java on Linux. The reason for choosing SQL Server is because that is the tool(+ Oracle) most DB administrators are familiar with.
If I could, I would choose PostgreSQL every time. But my clients do not have a person who is willing to learn to use Linux and PostgreSQL. Even fancy things like ultra fast backups with ZFS snapshots and PostgreSQL doesn't sell.
Anyway, working with SQL Server is fine, it's solid DB. But Microsoft should really invest time in a proper CLI tool that work on Linux.
Oracle seems to be the defacto DB at big installations, where SQL Server is common at shops that just want or already have Windows Admins.
The tools SQL Server provides are just GUI'fied versions of cmd line tools available on the other DB's mentioned here... so just saying "it's better because you can click on things" is not really a valid argument.
Not even mentioned above, but IBM's DB2 has a lot of GUI'fied admin tools as well as very robust terminal tools and a huge toolset available in the jtopen library. It's a good choice as well, although not as common in stand-alone installations (you'll encounter it more often bundled with things like as the backing db for AS/400 systems, etc)
RDBMSes that you pay for are still able to out perform free, community-developed systems [2]. I've done work on both the DBA and the developer side on Postgres, MySQL, and SQL Server, and I can tell you that if platform and cost were never an issue, I'd choose the latter every time.
[1] http://www.indeed.com/jobs?q=Java+SQL+Server [2] https://www.periscope.io/blog/count-distinct-in-mysql-postgr...