SQL Set Difference Without Joins

How would you access all the records in A but not in B without using JOIN, WHERE, EXCEPT, or subqueries?

Assume both tables use record_id as the comparison key. Return the records whose key exists in a and does not exist in b.

Output

1. One row per qualifying record, with columns record_id and record_value
2. Include only records present in a and absent from b
3. Order by record_id ascending