Storing large files in multiple schemas: BLOB or BYTEA

>Yeah, a pg_dump mode that dumped everything but large objects would be
nice.

There is option -b for pg_dump which controls whether large objects are
dumped or no. The problem is that with option -b it dumps all large objects
regardless of what schema you requested it to dump using option -n.
Otherwise it works fine.

>I'm now wondering about the idea of implementing a pg_dump option that
>dumped large objects into a directory tree like
> lobs/[loid]/[lob_md5]
>and wrote out a restore script that loaded them using `lo_import`.
>
>During dumping temporary copies could be written to something like
>lobs/[loid]/.tmp.nnnn with the md5 being calculated on the fly as the
>byte stream is read. If the dumped file had the same md5 as the existing
>one it'd just delete the tempfile; otherwise the tempfile would be
>renamed to the calculated md5.
>
>That way incremental backup systems could manage the dumped LOB tree
>without quite the same horrible degree of duplication as is currently
>faced when using lo in the database with pg_dump.
>
>A last_modified timestamp on `pg_largeobject_metadata` would be even
>better, allowing the cost of reading and discarding rarely-changed large
>objects to be avoided.

Definitely interesting idea with incremental backups.