LIKE '%' is not filtering out null columns

    @Test
    public void testLikeEverythingExpression() throws Exception {
        Connection conn = DriverManager.getConnection(getUrl());
        String ddl = "CREATE TABLE t (k1 VARCHAR, k2 VARCHAR, CONSTRAINT pk PRIMARY KEY (k1,k2))";
        conn.createStatement().execute(ddl);
        conn.createStatement().execute("UPSERT INTO t VALUES('aa','bb')");
        conn.createStatement().execute("UPSERT INTO t VALUES('ab','bc')");
        conn.createStatement().execute("UPSERT INTO t VALUES(null,'cc')");
        conn.createStatement().execute("UPSERT INTO t VALUES('dd',null)");
        conn.commit();
        
        ResultSet rs = conn.createStatement().executeQuery("SELECT * FROM t WHERE k1 LIKE '%'");
        assertTrue(rs.next());
        assertEquals("aa", rs.getString(1));
        assertEquals("bb", rs.getString(2));
        assertTrue(rs.next());
        assertEquals("ab", rs.getString(1));
        assertEquals("bc", rs.getString(2));
        assertTrue(rs.next());
        assertEquals("dd", rs.getString(1));
        assertEquals(null, rs.getString(2));
        assertFalse(rs.next());
        
        rs = conn.createStatement().executeQuery("SELECT * FROM t WHERE k2 LIKE '%'");
        assertTrue(rs.next());
        assertEquals(null, rs.getString(1));
        assertEquals("cc", rs.getString(2));
        assertTrue(rs.next());
        assertEquals("aa", rs.getString(1));
        assertEquals("bb", rs.getString(2));
        assertTrue(rs.next());
        assertEquals("ab", rs.getString(1));
        assertEquals("bc", rs.getString(2));
        assertFalse(rs.next());
        
        conn.close();
    }