Add scenarios that are more challenging for single-query solutions

[wickning1]

This article from .NET's Entity Framework documentation is really good at explaining why single queries are not always the answer.

https://learn.microsoft.com/en-us/ef/core/querying/single-split-queries

A cartesian explosion benchmark would be great.

[lroal]

I agree. The test case is too basic.
It should test nested one-to-many relations. Now it is only testing join from comments to post and user.
So a better test would be to to fetch users with posts with comments.
Most ORMs struggle with perfomance on this.

Also, why the LIMIT 1 ? It should be a larger number like 50 or 100.
I don't think it is neccessary to have so big database. It is more important to fetch more than 1 row.