Re: Hey! I thought this was fixed in 7.2.4

Josh Berkus <josh@agliodbs.com> writes:
> I thought this bug was fixed in 7.2.4:
> DBD::PgPP::st execute failed: ERROR:  Parent tuple was not found
> (a second VACUUM FULL ANALYZE succeeded)

IIRC, for 7.2.* we only attempted to fix the variants that resulted in
hard (repeatable) errors.  You've got the soft variant there.

The 7.3 sources explain that in fact this condition isn't an error, but
is an expected case in some situations (the example given is where a row
has been updated twice in the same transaction).  So the fix is to
downgrade the error to a DEBUG log message and adjust the code to let it
keep going rather than erroring out.  This change struck me as too risky
to put into 7.2.* for a nonfatal condition, though.  That part of VACUUM
is a real mare's nest, and I dislike messing with it in production
branches.

(I suppose that at this point we might consider the additional mods
proven by 7.3 field experience, and could consider back-porting them
if there are any further 7.2 releases.)
        regards, tom lane