databasefluttermigrationsqflitefloor

How can I alter my table column in Floor database with the help of Migration?

I Want update my table column in the Floor database with the help of changing my database version and run migrations. For example, I want to change column A to a nullable column! How can I achieve this goal? anybody can provide a sample code, please?

Solution

  • You can create a migration like this:

    
//Step 1 - Update the version to (ex: from 1 to 2) inside the database annotation
@Database(version: 1, entities: [Person, Task])
abstract class AppDatabase extends FloorDatabase {

//Step 2 - create the migration
final migration1to2 = Migration(1, 2, (database) async {
  await database.execute('ALTER TABLE person ADD COLUMN nickname TEXT');
});

//Step 3 - then add it to the code that initialize the DB
final database = await $FloorAppDatabase
    .databaseBuilder('app_database.db')
    .addMigrations([migration1to2])
    .build();

    full example of how to do it here: Migrations in Floor

    As for actual SQL to change it from not-null to nullable check this answer Modify Sqlite Table Column NOT NULL to NULL