- my $nr = $sth->execute($newbn, $fid, $oidbin, $$id);
- if ($nr == 0) { # may race with a clear_src, ensure new value exists
+ # eval since unique constraint may fail due to race
+ my $nr = eval { $sth->execute($newbn, $fid, $oidbin, $$id) };
+ if (!defined($nr) || $nr == 0) { # $nr may be `0E0'
+ # may race with a clear_src, ensure new value exists