Our company has made the decision to gradually leave sql server in favor of DB2. We have a wide variety of applications ( many acquisitions ) running on MSSql, Oracle, DB2 and others. I think pricing had a lot to do with it.
It will take a few years to migrate the application in my division from C# .net to Python/Java ( I think ) and the databases. I won't be with the company long enough to worry about it but wondered what thoughts you might have about DB2 versus Sql.
When I was in HP, we used to have DB2 , Oracle 10g and 11g (still they have, I think), and MS-SQL (lot of flavors, even SQL200). In my experience, the main reasons for these moves are:
-"Politics" (internal issues within the company with X or Y database product and that company)
-The guru guy(s) that writes .NET (or his team) is leaving the company
I am not a DB2 expert, and MS-SQL is not cheap anymore. But I am not aware of any huge cost saving thing that make a company jump to DB2 instead. Leaving MS-SQL for MySQL or MariaDB? maybe, but I personally find MySQL inferior in many ways. Not to start a DB engine war, but that's my opinion.