basalt_sqlite 0.0.2

basalt_sqlite: ^0.0.2 copied to clipboard

example/example.dart

import 'package:basalt/basalt.dart';
import 'package:basalt_sqlite/basalt_sqlite.dart';

/// Hand-written typed schema. In Stage 3 the CLI's `generate-schema` generates a
/// file exactly like this from the migrated database.
abstract final class Users {
  static const _t = 'users';
  static const id = PrimaryKey<int, Users>(_t, 'id', IntSqlType());
  static const name = ValueColumn<String, Users>(_t, 'name', StringSqlType());
  static const age = ValueColumn<int, Users>(_t, 'age', IntSqlType());
  static const table = TableRef<Users>(_t, [id, name, age]);
}

Future<void> main() async {
  final db = SqliteConnection.memory();

  await db.executeSql(
    'CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT NOT NULL, age INTEGER NOT NULL)',
  );

  // INSERT — typed, column-scoped values, all inside one transaction.
  await db.transaction((tx) async {
    await tx.execute(insertInto(Users.table)
        .value(Users.id.set(1))
        .value(Users.name.set('Bob'))
        .value(Users.age.set(30)));
    await tx.execute(insertInto(Users.table)
        .value(Users.id.set(2))
        .value(Users.name.set('Alice'))
        .value(Users.age.set(17)));
    await tx.execute(insertInto(Users.table)
        .value(Users.id.set(3))
        .value(Users.name.set('Carol'))
        .value(Users.age.set(42)));
  });

  // SELECT — one `map` for any shape. Here a record; the reader is typed.
  final adults = await db.fetch(
    from(Users.table)
        .select([Users.name, Users.age])
        .where(Users.age.ge(18))
        .orderBy(Users.age.desc())
        .map((r) => (r.get(Users.name), r.get(Users.age))),
  );
  print('Adults (name, age): $adults'); // [(Carol, 42), (Bob, 30)]
  for (final (name, age) in adults) {
    print('  $name is $age'); // statically (String, int)
  }

  // UPDATE
  final updated = await db.execute(
      update(Users.table).value(Users.age.set(31)).where(Users.name.eq('Bob')));
  print('Rows updated: $updated');

  // DELETE
  final deleted =
      await db.execute(deleteFrom(Users.table).where(Users.age.lt(18)));
  print('Rows deleted: $deleted');

  final names = await db.fetch(
    from(Users.table).orderBy(Users.name.asc()).map((r) => r.get(Users.name)),
  );
  print('Remaining names: $names'); // [Bob, Carol]

  await db.close();
}