 }
 
 extension PlaceAnnotation: Diffable {
+    // The `primaryKeySortedDiff` observable documents that this method should
+    // return self if we wish elements to be reused during the computation of
+    // the diff.
     func updated(with row: Row) -> Self {
         place = Place(row: row)
         return self

import GRDB
import RxGRDB

final class PlaceAnnotation: NSObject, MKAnnotation {
    var place: Place {
        willSet { willChangeValue(forKey: "coordinate") }
        didSet { didChangeValue(forKey: "coordinate") }
    }

}

extension PlaceAnnotation: Persistable {
    static let databaseTableName = Place.databaseTableName
    
    func encode(to container: inout PersistenceContainer) {
        place.encode(to: &container)
