Jeremiah Jahn <jeremiah(at)cs(dot)earlham(dot)edu> writes:
> when I run the following two commands all of my OIDs for my blobs (about
> 5.5 million of them) no longer reference anything in pg_largeobject.
> All of the loid values change.
pg_dump/pg_restore do not (and cannot) arrange for large objects to have
the same OIDs after restore as they had before. What they do try to do
is update references to the large objects to have the new OID values.
Last I checked, they look in columns of types "oid" and "lo" (if "lo"
exists) for such references. Maybe you were engaging in some type
punning, like storing your references in int4 or int8 columns?
regards, tom lane