Writing tests should assure us that the code created by us is working correctly. Often we point out the code coverage factor and if we have 100% we can say that implemented solutions are correct. Are you sure? Maybe there is a tool that can give us more accurate feedback?
In the most of systems need to save data somewhere and in some way. ORM (Object-Relational Mapping), is the way of mapping the system to the database. ORM is the layer between database and application which deals with creating, updating, reading and deleting.