I’m learning PostgreSQL and want to understand the exact order in which SQL statements are evaluated. After researching, I found the following evaluation order:

 1. FROM 
 2. ON 
 3. JOIN 
 4. WHERE 
 5. GROUP BY 
 6. HAVING
 7. SELECT 
 8. AS  
 9. DISTINCT 
 10. ORDER BY 
 11. LIMIT / OFFSET   

Based on this order, it seems that when I create an alias, I can’t use it in the clauses that are evaluated before the SELECT statement. However, I’m confused about how this works with subqueries. For example:

SELECT first_name, last_name
    FROM customer AS c
    WHERE EXISTS(
    (SELECT * FROM payment AS p
    WHERE p.customer_id = c.customer_id
    AND amount > 11)
    );

How can the subquery use the alias c and, how does the subquery get access to the alias c before it is created?

Could someone provide insights how does this work?

Thank you in advance for the help!