I have to concatenate 2 columns and put the value. but the problem is even if both the values are null it is still giving (:) as per below syntax. is there anyway we can remove column in the output if both values are null.

```
listagg(AP.ISSUE_ID||':'||ISS.ISSUE_DESCRIPTION ,'; ') within group(order by AP.ISSUE_ID||':'||ISS.ISSUE_DESCRIPTION) DESCRIPTION,

```