Hi there!
aliases must be strings. If your column alias contains space, special character, or is a number, then grab it within a backticks. See example below:
select
order_id, -- No Alias - Works
order_id as ORDER_ID, -- String - Works
-- order_id as "ORDER_ID", -- Double quotes - Syntax Error
-- order_id as 'orderid', -- Single quotes - Syntax Error
-- order_id as _@+$, -- Specia chars - Syntax Error
order_id as `_@+$` -- Backticks - Works
from my_view
Output :

Table alias should have been used without quotes as well 🙂
Cheers!