BLOB DBI func() interface under postgres

Hello,

In DBD::Pg one can read (line 134):

    $lobj_fd = $dbh->func($lobjId, $mode, 'lo_open');

But how is the LOB retrieved in the first place? If I pass the OID of an
existing LOB instance from a table the returned $lobj_fd is null. What
kind of $lobjId is one supposed to pass to this function to open a LOB?

The aim is to be able to read a LOB from a postgres DB without having to
lo_export the object to a file first. Can that be done with the
$dbh->func() interface? (using lo_open, lo_read, etc ..)

TIA

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Louis-David Mitterrand - ldm@apartia.org - http://www.apartia.fr

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