yawn There are other databases systems doing that, no need to depend on Oracle. For example: http://erlang.org/faq/mnesia.html which is also associated with a programming language known for its quality distributed computing.
Removing contributions to the Linux kernel? I don't think so. The kernel is free software and people contribute to it knowing that it is free software, so they cannot hold any code hostage. Once you release as free software, you give up that control.
I’ve never heard of anyone who actually uses mnesia for real or would consider it prime-time. I’m no Oracle fanboy but comparing their DB to mnesia is like comparing an oil rig driller to a fisher price screwdriver.
> never heard of anyone who actually uses mnesia for real
I didn't till I had to become one of them this year. Mnesia is real, it's prime time, but not in place of something like Oracle.
> comparing an oil rig driller to a fisher price screwdriver.
Better analogy would be Comparing SQL Server to Redis. Mnesia is, at it's heart, a(n optionally) Transactional K-V lookup that can be run distributed. It's use case it works VERY well, but I wouldn't consider it a substitute for Relational storage.
Basically, as soon as something is released as free software, you must have the 4 freedoms: use, study, share, improve. This means, that it is not important, who contributed the code and what else they did, in the context of using that code in any of the 4 freedoms ways. It frees the code from the control of the creator in that sense and the creator cannot take it back. Anyone who releases as free software will give up such control.
Oracle once having provided something to free software (My guess: They only did it because the GPL forced them to.) does not mean, that we have to like Oracle. These two things are not connected.
I am not sure about the state of Mnesia, however, I wrote, that it is an example. If I had found a Wikipedia list of DDBMS, I would have posted that. However, I am sure knowledgeable people will be able to name a few more.
Removing contributions to the Linux kernel? I don't think so. The kernel is free software and people contribute to it knowing that it is free software, so they cannot hold any code hostage. Once you release as free software, you give up that control.