-- [VALVES]

create type valves_type as enum ('PRV', 'PSV', 'PBV', 'FCV', 'TCV', 'GPV');

create table valves
(
  id varchar(32) primary key references _link(id)
, node1 varchar(32) references _node(id) not null
, node2 varchar(32) references _node(id) not null
, diameter numeric not null
, type valves_type not null
, setting numeric not null
, minor_loss numeric not null
);