Select query select with Substr returns NULL

I am trying to query the name field in the Oracle DB like below

select NAME, Substr(NAME,1,instr(NAME,' ') - 1) as SHORTNAME from rm_room

what I am trying is if the Name field has space between the string the select only charcters on the left of the space. I am expecting the above query to return

but the issue is if the name field doesnot have space then it is returning null in the SHORTNAME Field

Can we use if condition in the select clause if so how can I check that

>Solution :

you could just use the NVL function which sets a default value instead of null

select NAME, NVL(Substr(NAME,1,instr(NAME,' ') - 1),NAME) as SHORTNAME from rm_room