Proposed change to spacewalk's lookup_evr function

lookup_evr.sql

-- oracle equivalent source sha1 231a317e7ec144399cc913861269e968d41b8840
--
-- Copyright (c) 2008--2012 Red Hat, Inc.
--
-- This software is licensed to you under the GNU General Public License,
-- version 2 (GPLv2). There is NO WARRANTY for this software, express or
-- implied, including the implied warranties of MERCHANTABILITY or FITNESS
-- FOR A PARTICULAR PURPOSE. You should have received a copy of GPLv2
-- along with this software; if not, see
-- http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
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-- Red Hat trademarks are not licensed under GPLv2. No permission is
-- granted to use or replicate Red Hat trademarks that are incorporated
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create or replace function
lookup_evr(e_in in varchar, v_in in varchar, r_in in varchar)
returns numeric
as
$$
declare
    evr_id  numeric;
begin
    select id
      into evr_id
      from rhnPackageEVR
     where ((epoch is null and e_in is null) or (epoch = e_in)) and
           version = v_in and
           release = r_in;

    if not found then
        evr_id := nextval('rhn_pkg_evr_seq');

        insert into rhnPackageEVR(id, epoch, version, release, evr)
            values (evr_id, e_in, v_in, r_in, evr_t(e_in, v_in, r_in))
            on conflict do nothing;

        select id
            into strict evr_id
            from rhnPackageEVR
            where ((epoch is null and e_in is null) or (epoch = e_in)) and
               version = v_in and release = r_in;
    end if;

    return evr_id;
end;
$$ language plpgsql;