Generating single point query from ast creates an invalid query

The generated query looks like the following which is invalid:

```sql
select * from test_single_points_with_nulls where ((time = 1410368584848890u) AND (sequence_number = 10001)) AND ((time < 1410368584848890000) AND (time > 1410368584848890000))
```
Should that be "if this is a single point query..."?