Liste todos os índices Postgres
select * from pg_indexes
where schemaname like '<schema-name>' and tablename like '<table-name>'
Lazy Lizard
select * from pg_indexes
where schemaname like '<schema-name>' and tablename like '<table-name>'-- This will also return use the hidden index that automatically created by primary key and unique....
SELECT relname, relkind
FROM pg_class
WHERE relkind = 'i';