-- [TANKS] create type tanks_overflow as enum ('YES', 'NO'); create table tanks ( id varchar(32) primary key references _node(id) , elevation numeric not null , init_level numeric not null , min_level numeric not null , max_level numeric not null , diameter numeric not null , min_vol numeric not null , vol_curve varchar(32) references _curve(id) , overflow tanks_overflow ); -- unset vol_curve when delete curve