begin;

create table foo (
    one int,
    two int,
    three int,
    primary key (one, three)
);

insert into foo values (4, 5, 6);

select * from foo order by 1, 3;

select c.relname, a.attname, a.attnum from pg_attribute a join pg_class c on (c.oid = a.attrelid) where c.relname='foo' and attnum >= 0 order by attnum;
select indnatts, indkey, indisprimary from pg_index i join pg_class c on (c.oid = i.indrelid) where c.relname='foo';

alter table foo drop column two;

select c.relname, a.attname, a.attnum from pg_attribute a join pg_class c on (c.oid = a.attrelid) where c.relname='foo' and attnum >= 0 order by attnum;
select indnatts, indkey, indisprimary from pg_index i join pg_class c on (c.oid = i.indrelid) where c.relname='foo';

select * from foo order by 1, 3;

rollback;