The following bug has been logged online:

Bug reference: 2823
Logged by: Gregor
Email address: gtm2 (AT) interia (DOT) pl
PostgreSQL version: 8.2, 8.1
Operating system: Windows
Description: API largeobject calls
Details:

Hello,
API funtions lo_open, lo_write, lo_import don't work.
While lo_create returns positive integr value ( and the record with this
loid is inserted into pg_largeobject table) lo_open return always zero
value
with when this non-zero positive loid value obtained from lo_create is
passed to lo_open. And lo_write returns -1 when this zero value obtained
from lo_open is passed to lo_write.

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"Gregor" <gtm2 (AT) interia (DOT) pl> writes:
You need to do lo_open/lo_write/etc inside a transaction block, because
the LO handle returned by lo_open is only good until end of transaction.
(And yes, zero is a valid handle.) See the example program in the docs:
http://www.postgresql.org/docs/8.2/s...amplesect.html
and note the begin/commit commands it issues.

regards, tom lane

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