I seem to recall neo4j (could be it was another nosql db/company) had some strange ideas about the agpl. Of course if the drivers are covered by agpl and linked into your application, then you might have to create a new api "border" (eg:HTTP REST) between whatever code you want to license differently and the agpl server. I don't think the agpl should be a problem in most cases - at any rate you don't have to contribute patches up-stream, only to those of your users that ask for the code (if any). Unless upstream is also using your service, that is.

A perhaps more interesting question is how they manage contributions and pull requests - if i'm using the server under agpl, it seems natural to contribute code under agpl. But now that code can't be used in the commercially licensed upstream "fork" unless that fork is sold under the agpl... So either contributors will have to donate code, or sell code to upstream for use in the "closed" project.

I could see that get a bit hairy with user-contributed bug fixes?

So far, AGPL has not been tested in court. GPL has. The scope of Derivative Works (reach) has as well (but the case law in this area is more complicated than most open source developers are aware of since copyright law is understood differently based on which federal circuit court hears the case). The more challenging consideration for me is the AGPL/Apache (DB/Driver) method that these companies are using -- and especially when you have Apache licensed community contributions (these apparently violates AGPL's own terms). I see this as an area that can backfire against the open source community -- and indeed I'd also like to know if FSF, SFLC, or GPL-violations takes a position on the use of Apache drivers to AGPL DBs. If so, it would be best for the open source community to know about this soon rather than after many have placed themselves in a position where their best option is to pay the vendors that have somehow managed to achieve lock-in. Ironically, this is the opposite of the goals that many in the open source community endorse. So if FSF takes a strict position on AGPL, it could accidentally result in the opposite of the freedoms we have been working for.

I'm also fascinated when companies use a license and then state in their FAQ that they didn't really mean all the terms of the license. If this comes up in court, the judge might take the FAQ into account and interpret the intent of the licensor, or might just look at the license text itself. It'll be interesting to see what happens. My advice for now is to assume the text of the license to be what the licensor intended and my hope is that companies that use open source licenses simply use the licenses that match what they mean. If they really mean that they want you to pay, they should just be clear about it and people can decide if they want to pay.

Well in the case of companies like Google or Facebook, they might actually modify the database for various of reasons (e.g. internal policy, speed, etc). I don't have first hand experience with modifying databases so I thought I would ask :)

If someone modified the database and deployed it publicly (or as part of a webapp that was deployed publicly), they'd need to share the modified source, yes. AGPL is roughly GPL but where the traditional definition of "shipping software" is expanded to include deploying on a network.

My guess is that they have two motivations, both of which are fairly traditional GPL motivations: 1) sell AGPL exceptions to commercial licensees; and 2) prevent a competitor from making a private commercial fork, where the competitor improve the DB and licenses their version to clients, without sharing the source to their improvements.

To be pedantic: deployed it a an external service, not necessarily a public service (I suppose to a legal entity that would not normally share license rights, such as an inividual not part of the organisation or to another organisation). Those external users would have to be given an option to access the full source with modifications.

As for the "part of a web service"-bit, I'm not sure what the agpl's actual "reach" is. My understanding is that with a (modified) db under agpl powering eg a web app runing in php, the end users (accessing only the web server) would not be entitled to the db source. If the agpl covered the web srrver itself or a php library on the other hand, the users would be entitled to that code?

Similarly if one sold a modified db-as-a-service, modifications would be covered by the agpl.

While its interesting to theorize about databases and AGPL, I am rather sure there hasn't been any actually case or a legal reason to think that the database would become a derivative work when used together with a webserver.

If it was, the EULA for SQL server and oracle would have to include copyright permission for derivative works. That we do not see that should be a clear sign that the scope of copyright has not reached that far yet.