I have data inside a table's column. I SELECT DISTINCT of that column, i also put LTRIM(RTRIM(col\_name)) as well while writing SELECT. But still I am getting duplicate column record. 

How can we identify why it is happening and how we can avoid it?

I tried RTRIM, LTRIM, UPPER function. Still no help.

Query:

```
select distinct  LTRIM(RTRIM(serverstatus)) 
from SQLInventory

```

Output:

```
Development
Staging
Test
Pre-Production
UNKNOWN
NULL
Need to be decommissioned
Production

Pre-Produc​tion
Decommissioned
Non-Production
Unsupported Edition

```