Re: FKs + partial indexes?

Andrew Dunstan <andrew@dunslane.net> writes:
> create table constants (type text, id int primary key, value text);
> create unique index x_const_idx on constants(id) where type = 'x';
> create table client (id serial primary key; xid int references 
> constants(id) using x_const_idx);

This seems like a solution in search of a problem.  Why wouldn't you
just use separate reference tables?  Adding such a concept would break
more things than I even want to think about (information_schema for
starters).
        regards, tom lane