Dart APIunself_local_databaseCollectionupdated updated property Null safety DateTimeColumn updated Implementation DateTimeColumn get updated => dateTime()(); unself_local_database unself_local_database Collection updated property Collection class Constructors Collection Properties created createRule customConstraints deleteRule dontWriteConstraints extra hashCode id isStrict listRule name primaryKey runtimeType system tableName type uniqueKeys updated updateRule viewRule withoutRowId Methods blob boolean dateTime int64 integer intEnum noSuchMethod real text textEnum toString Operators operator ==