Postgresql UUID Bloom index support (best for UUIDv4) (https://www.postgresql.org/docs/current/bloom.html)

uuid-bloom.sql

create extension "uuid-ossp";
-- https://www.postgresql.org/docs/current/bloom.html
create extension bloom;

CREATE or replace FUNCTION hashuuid(u uuid) RETURNS integer AS $$
DECLARE
   a bytea := uuid_send(u);
BEGIN
   RETURN (get_byte(a, 3) << 24) + (get_byte(a, 2) << 16) + (get_byte(a, 1) << 8) + get_byte(a, 0);
END;
$$ LANGUAGE plpgsql IMMUTABLE;

CREATE OPERATOR CLASS uuid_bloom
DEFAULT FOR TYPE uuid USING bloom AS
    OPERATOR    1   =(uuid, uuid),
    FUNCTION    1   hashuuid(uuid);

-- create index on "table" using bloom(column1,column2,column3) with (length = 20)