Problems with large objects

Hi,

I am rather new to Postgresql and am having trouble with
some aspects of large objects. I am coming from a MySQL
backgroun where a longblob could just be another column so
please excuse my ignorance.

I am creating objects using the DBI interface and inserting
data which works well. I am however having trouble
deleting blob data from the db.
test=> \lo_list
Large objects
ID | Description
-------+-------------
89803 |
90068 |
(2 rows)

test=> \lo_unlink 89803
ERROR: pg_description: Permission denied.
test=>

Do I have to grant any user who needs blobs access to a
system table (pg_description)? If so, how much damage can
they do?

Also, I have been reading about tforeign keys which looks
very neat. Can these be extended to large objects. For
example:
table files
filename varchar(120) not null,
data oid
delete from files where filename='badfile.txt';
Can I have the delete statement above knock out the
associated large object if one exists?

Thanks in advance,
Shane

--
Shane Wegner: shane(at)cm(dot)nu
http://www.cm.nu/~shane/
PGP: 1024D/FFE3035D
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