Repeat rows with in the GROUP as per max value of that group using SQL (PostgreSQL)

Question

Input

question_id	option_rank
1	1
1	2
2	1
2	2
2	3

How to get below output using SQL. Position will be new fabricated column in the output. Basically a given option rank to be repeated n times, n being max option rank of a given question.

question_id	option_rank	position
1	1	1
1	1	2
1	2	1
1	2	2
2	1	1
2	1	2
2	1	3
2	2	1
2	2	2
2	2	3
2	3	1
2	3	2
2	3	3

Created numbers table with single column consisting of id from 1 to 1000(1000 rows) and then joined it with above question table.

Answer 1

We can use a self join here:

SELECT t1.question_id, t1.option_rank, t2.option_rank AS position
FROM yourTable t1
INNER JOIN yourTable t2
    ON t2.question_id = t1.question_id
ORDER BY 1, 2, 3;