@Test
  void existsWithLimit() {
    // empty
    check(!repository.findAll().limit(1).exists());
    check(!repository.findAll().limit(2).exists());

    repository.insert(generator.get().withId("id1").withValue("v1"));
    check(repository.findAll().limit(1).exists());
    check(repository.findAll().limit(2).exists());

    check(repository.find(string.id.is("id1")).limit(1).exists());
    check(!repository.find(string.id.isNot("id1")).limit(1).exists());
    check(repository.find(string.id.is("id1")).limit(2).exists());
  }
Testing {@code exists} functionality, ie wherever at least one record could be found
for a given criteria.
criteria/common/test/org/immutables/criteria/typemodel/ExistsTemplate.java