I've had recently a conversation with Qlik support about Direct Query issue. I was using a DETACH field type in version 11 and initial release of version 12. Support had made an assumption:
It's strange that DETACH field type disappeared from the help by some miracle. Or is it a backward compatibility issue? Because, DETACH is still exists in version 11 help (see attachment).
Having online help is very good, but, I think, Qlik has to support versioning there with freeze mechanism for former versions.