@Test
public void joinColumnsMismatch () { 

    builder.table("j6").colInt("c1").colString("c2", 10).joinTo("t2").on("c2", "c1").and("c1", "c2");
    Collection<AISValidationFailure> failures = builder.unvalidatedAIS().validate(validations).failures();
    Assert.assertEquals(2, failures.size());
    
}