Question

Fellows,
I have a query as follows:

SELECT A.ID, B.ID, (HUGE SUBQUERY) as HS
FROM TABLE_A JOIN TABLE_B ON A.ID = B.ID
WHERE (HUGE SUBQUERY) > 0

I’d like to avoid repeating the subquery.
Is there any way to rewrite my WHERE as something like

WHERE HS > 0

Or I must turn my subquery into a join?

Answer 1

You could use a CTE:

WITH cteHS AS (
    SELECT xxx AS Value
        FROM Huge Subquery
)
SELECT A.ID, B.ID, cteHS.Value as HS
    FROM TABLE_A, cteHS
        JOIN TABLE_B ON A.ID = B.ID
    WHERE cteHS.Value > 0