Samuel Trégouët <samuel.tregouet@logilab.fr> [Tue, 15 Dec 2015 10:13:55 +0100] rev 11021
[dataimport] massive_store: do not drop constraints with `cascade` since it breaks things
We want to be able to restore constraints at the end of the import. If
they are silently dropped due to a CASCADE, we can't do that.