Dart APIunself_local_databaseFieldcollectionId collectionId property Null safety TextColumn collectionId Implementation TextColumn get collectionId => text().references(Collection, #id)(); unself_local_database unself_local_database Field collectionId property Field class Constructors Field Properties collectionId created customConstraints dontWriteConstraints extra hashCode id isStrict name primaryKey required runtimeType system tableName type unique uniqueKeys updated withoutRowId Methods blob boolean dateTime int64 integer intEnum noSuchMethod real text textEnum toString Operators operator ==