select coalesce(max(v.sort_order),0)
from acs_enum_values v
where v.attribute_id = :attribute_id
delete from acs_enum_values
where attribute_id = :attribute_id
and sort_order = :sort_order
update acs_enum_values
set pretty_name = :pretty_name
where attribute_id = :attribute_id
and sort_order = :sort_order
insert into acs_enum_values
(attribute_id, sort_order, enum_value, pretty_name)
select :attribute_id, :sort_order, :pretty_name, :pretty_name
from dual
where not exists (select 1
from acs_enum_values v2
where v2.pretty_name = :pretty_name
and v2.attribute_id = :attribute_id)