db.select(sql).dependsOnOperator().getXXX() doesn't seem to work

Hi,

I have the following piece of code that doesn't seem to work as I want:

``` java
updateObservable = Observable.interval(0, 10, TimeUnit.SECONDS)
.doOnNext(s -> System.out.println("try " + s))
.lift(db
.select("SELECT id FROM mytable ORDER BY updated_at ASC")
.dependsOnOperator()
.getTupleN()
)
.doOnNext(s -> System.out.println("result " + s));

updateObservable.subscribe();
```

This prints out:

```
try 0
try 1
...
```

Although this seems to work fine:

``` java
updateObservable = Observable.interval(0, 10, TimeUnit.SECONDS)
.doOnNext(s -> System.out.println("try " + s))
.lift(db
.select("SELECT id FROM mytable WHERE id <> ? ORDER BY updated_at ASC")
.parameterOperator()
.getTupleN()
)
.doOnNext(s -> System.out.println("result " + s));
updateObservable.subscribe();
```

Because it prints the following:

```
try 0
result TupleN [values=[18]]
result TupleN [values=[16]]
result TupleN [values=[17]]
try 1
result TupleN [values=[18]]
result TupleN [values=[16]]
result TupleN [values=[17]]
...
```

**Am I doing something wrong in the first example ?**

FYI I've simplified the above example but what I really want to do is to continuously poll that request and process its elements. It would probably look like that:

``` java
updateObservable = Observable.interval(0, 1, TimeUnit.NANOSECONDS)
.onBackpressureLatest()
.lift(db
.select("SELECT id FROM mytable ORDER BY updated_at ASC")
.dependsOnOperator()
.getTupleN()
)
.> compose(new MyTableTransformer())
.lift(db
.update("UPDATE mytable SET updated_at = ? WHERE id = ?")
.parameterOperator()
);

updateObservable.subscribe();
```

Thanks