Improve performance of db-benchmark query 8

### Is your feature request related to a problem or challenge?

Query 8 in db-benchmark is slower than other queries
https://github.com/MrPowers/mrpowers-benchmarks

The query is as follows

```sql
select id6, largest2_v3 from
(select id6, v3 as largest2_v3, row_number() over (partition by id6 order by v3 desc) as order_v3
from x
where v3 is not null) sub_query
where order_v3 <= 2
```

### Describe the solution you'd like

* Profile / analyze this query
* Improve performance

It might be the part `row_number() over (partition by id6 order by v3 desc)` or rather the sorting is the most expensive.

`

### Describe alternatives you've considered

_No response_

### Additional context

_No response_