The repository is the translator layer. You simply ask your repository to create an item to the datastore and the repository translates that request to SQL or to any other querying language. Your application does not need to know the type of the database or how to interact with it. It just communicates with the repository that translates the generic commands to the language the database understands.
Table of contents
Repository Patterns: Databases Made EasyRepositories in PracticeIntroduction to Red BirdSort: