Database Testing in Rails

I'm using Rails 4 and the testing framework with which it ships.

I'm using a relational database which needs to be rigorously tested for internal consistency. In this case, it's a sports statistics database with player stats that are updated nightly.

I need to run tests like the following when new data arrives each night:

--That the sum of player stats equals the team's.

--That the sum of team stats equals the league's.

--That the sum of wins and losses equals games played.

--etc.

For now I'm copying my development database over to testing and running these alongside my unit tests in the /test/models/ directory.

This is an awkward set-up as my database testing code isn't comprised of unit tests in their proper sense, and it doesn't rely on fixtures as the Rails documentation suggests this folder be used for.

My question is: How and where in Rails should I perform database testing like I describe above?