Monitoring tables data collection is unstable when attaching or detaching database [CORE2482] #2895
Commented by: @AlexPeshkoff
The bug was found when working with 2.1. I'm not absolutely sure that all found problems can be reproduced with 2.5 - at least a problem with missing tdbb_status_vector was already solved in it. But given checks are correct for 2.5 too, and even if AST is not called at the moment when their conditions are true, it's much safer to have this checks then haev a risk to run snapshot's dump with incomplete attachment's data.