Hi I am working on one query, what I want to do is, whenever output comes in negative value,
I want to make it null, following is my query, can anyone help me with this ?

```
select (to_char((coalesce(14515200/3600000,0) - (coalesce(30512.65/3600,0) - (coalesce(1800/3600,0) + (coalesce(1800/3600,0))))),'FM99,999,999,999'))::character varying as test

```