Alvaro Herrera <alvherre@commandprompt.com> writes:
> More interesting, however, is the fact that the XMAX_COMMITTED bit is
> never set either. I guess the rows are deleted by a different mechanism
> (tuptoaster probably) -- it isn't obvious how this works just by looking
> at tqual.c. It seems to do nothing at all.
I have some vague recollection that the only reason we do any xmin/xmax
checking at all for a TOAST tuple is to support tuple motion caused by
old-style VACUUM FULL. Jan might remember better.
regards, tom lane
