Sync vs Async

Every method that is not executed in O(1) time has a background method associated with it (i.e. fetch and fetchInBackground, save and saveInBackground). Most of the sync methods throw, while the async methods have a completion block with an error as a parameter.

// Sync
let movies = try Movie.fetchAll()

// Async
Movie.fetchAllInBackground({ (movies, error) in
    guard error == nil else{
        // handle error
        return
    }
    print("Fetched \(movies.count) movies.")
})

##Differences

#####Threads: Sync methods execute on the current thread while Async methods execute on a background thread associated with the model

#####Error Handling: Sync methods throw, while the async methods have a completion block with an SQLiteModelError as a parameter.