Question

The below query is giving error:

SELECT DISTINCT dealer_state
FROM A
WHERE country='SS' 
UNION
SELECT DISTINCT dealer_state
FROM B
WHERE country='SS'
ORDER BY upper(dealer_state)

How to sort using upper(column) in order by clause?

Answer 1

Assuming that the “error” your query is giving is that it’s not ordering records from B amongst records from A as you had expected, you need to make your UNION query a subquery to one that performs the ordering:

SELECT dealer_state FROM (
    SELECT dealer_state FROM A WHERE country='SS' 
  UNION
    SELECT dealer_state FROM B WHERE country='SS'
) t
ORDER BY upper(dealer_state)