NestJSTransactions đảm bảo multiple DB operations thành công hoặc rollback toàn bộ.
Cách 1 — QueryRunner (recommend cho complex transactions):
typescript
const queryRunner = this.dataSource.createQueryRunner();
await queryRunner.connect();
await queryRunner.startTransaction();
try {
await queryRunner.manager.save(User, user);
await queryRunner.manager.save(Profile, profile);
await queryRunner.commitTransaction();
} catch (err) {
await queryRunner.rollbackTransaction();
throw err;
} finally {
await queryRunner.release();
}Cách 2 — EntityManager.transaction() (cleaner cho simple cases):
typescript
await this.dataSource.transaction(async manager => {
await manager.save(User, user);
await manager.save(Profile, profile);
// Tự động rollback nếu throw
});Cách 3 — @Transaction decorator (deprecated trong TypeORM 0.3+, không dùng).
Lưu ý: không mix repository từ DI và queryRunner.manager trong cùng transaction — chúng dùng connection pool khác nhau.
Transactions ensure all DB operations succeed or roll back entirely.
Option 1 — QueryRunner (recommended for complex transactions):
typescript
const qr = this.dataSource.createQueryRunner();
await qr.connect();
await qr.startTransaction();
try {
await qr.manager.save(User, user);
await qr.commitTransaction();
} catch { await qr.rollbackTransaction(); throw; }
finally { await qr.release(); }Option 2 — EntityManager.transaction():
typescript
await this.dataSource.transaction(async manager => {
await manager.save(User, user);
// Auto-rollback on throw
});Pitfall: do not mix DI repositories and queryRunner.manager in the same transaction.