Harald Krake <harald(at)krake(dot)de> writes:
> while running a "vacuumdb -z" I got the following error message:
> ERROR: simple_heap_update: tuple concurrently updated
> vacuumdb: vacuum jartifice failed
Is it likely that someone else was doing the same thing in another
session? This failure is known to occur if two backends concurrently
ANALYZE the same table --- the second one to try to update the
pg_statistics row fails because of the concurrent write. It's quite
harmless, except for preventing the rest of the VACUUM command from
completing.
regards, tom lane