Re: pqlib large object error

On Tue, 2008-06-10 at 16:49 -0400, Tom Lane wrote:
> Edward Amsden <amsden_linux@embarqmail.com> writes:
> > On Tue, 2008-06-10 at 14:29 -0400, Tom Lane wrote:
> >> Edward Amsden <amsden_linux@embarqmail.com> writes:
> >>> I cannot seem to figure this error message out:
> >>> 
> >>> ERROR:  duplicate key value violates unique constraint "pg_largeobject_loid_pn_index"
> >> 
> >> Huh, that shouldn't happen.  Is it repeatable?
> 
> > Yes. It happens every time the program runs, no matter what db or user,
> > tried unix socket and tcp connect
> 
> >> What PG version
> >> is your server?
> 
> > 8.3.1, running on Ubuntu Linux
> 
> Hmph.  The only thing I can think of is that that index is corrupt,
> but it seems unlikely that it would be so in all databases.  What
> happens if you REINDEX pg_largeobject?
The error has disappeared. Now it can't write to the object. lo_open
seems to be successful, but lo_write is failing with:
> ERROR:  invalid large-object descriptor: 0
0 is a valid value (I checked) but it appears it cannot write to the object. lo_open should return a negative value if
itcannot create the handle
 

Here is my code:


if (PQstatus(connect1) == CONNECTION_OK) {    lo_1 =  lo_creat(connect1, INV_READ|INV_WRITE);    if (lo_1 > 0) {
lo_1_fd= lo_open(connect1, lo_1, INV_READ|INV_WRITE);        written = lo_write(connect1, lo_1_fd, filedata, (size_t)
filelen);       if (written == filelen) {            printf ("Write successful, %d bytes written.\n", written);
}else if (written < 0) {            printf ("Write unsuccessful: %s\n", PQerrorMessage(connect1));        } else {
     printf ("Write partially successful. %d of %d bytes written.\n",
 
written, filelen);        }    } else {        fprintf (stderr, "Unable to create large object: %s\n",
PQerrorMessage(connect1));    }} else {    fprintf (stderr, "Unable to open connection: %s\n",
PQerrorMessage(connect1));}

Let me know if it's unreadable, my mail client can do funny things with
indents.

>             regards, tom lane