@Test
public void simpleConjunctionOfDisjunctions() {

    Set<String> dnf = createDisjunctiveNormalForm(createSimpleConjunctionOfDisjunctionsQuery());
    assertEquals(4, dnf.size());
    assertTrue(dnf.contains("c1=v1 AND c3=v3"));
    assertTrue(dnf.contains("c1=v1 AND c4=v4"));
    assertTrue(dnf.contains("c2=v2 AND c3=v3"));
    assertTrue(dnf.contains("c2=v2 AND c4=v4"));
}