Re: tuptoaster.c must *not* use SnapshotAny

> > How do we know, that a (newly) FrozenXid tuple does not still have 
> > a (visible) duplicate ?
> 
> It's *not* visible, if you are applying any visibility checks whatever.
> But SnapshotAny bypasses all visibility checking.

I am concerned about the case where VACUUM FULL:
1. inserts heap tuple to new location using FrozenXid
2. updates original heap tuples's xmax

What if we crash/abort between step 1 and 2 but we used FrozenXid for 1.
Don't know if we actually do this, but imho we are only allowed 
to use FrozenXid for an inplace vacuum operation.

Andreas