What TDD/BDD tests should be writen to test an ORM

So I'm writing an ORM for NodeJS and using Mocha + Chai to test it.

What I want to know is, what tests I should write to it, insertion tests should also have a querying test so I can check if the tool has inserted the correct data?

Also, how should I organize the tests? Any example of how to begin to write those tests? (Not an example of how to write tests, but how to organize and plan the tests for an ORM)