What are the two main ways to run a database transaction in TypeORM with NestJS?

Q: What are the two main ways to run a database transaction in TypeORM with NestJS?

// Option 1 — dataSource.transaction() (recommended) // Auto commits on success, auto rolls back on exception @Injectable() export class OrdersService { constructor(private dataSource: DataSource) {} async placeOrder(dto: CreateOrderDto): Promise { return this.dataSource.transaction(async manager => { const order = manager.create(Order, dto); await manager.save(order); await manager.decrement(Product, { id: dto.productId }, 'stock', dto.qty); return order; }); } } // Option 2 — QueryRunner (manual control) async placeOrder(dto: CreateOrderDto): Promise { const qr = this.dataSource.createQueryRunner(); await qr.connect(); await qr.startTransaction(); try { const order = qr.manager.create(Order, dto); await qr.manager.save(order); await qr.manager.decrement(Product, { id: dto.productId }, 'stock', dto.qty); await qr.commitTransaction(); return order; } catch (e) { await qr.rollbackTransaction(); throw e; } finally { await qr.release(); // always release back to connection pool } } dataSource.transaction() — preferred for most cases; handles commit and rollback automatically. QueryRunner — use when you need savepoints, multiple nested transactions, or manual commit timing. Always call qr.release() in a finally block — failing to release leaks connections from the pool. Never use injected Repository instances inside a transaction — use manager.getRepository(Entity) instead. Inject DataSource directly into the service; it is always available from the TypeORM module.

Difficulty: 5/10

TypeORM transactions, NestJS integration, QueryRunner

Use dataSource.transaction() with a callback for automatic commit and rollback — the recommended approach for most cases. Use QueryRunner for manual control when you need savepoints, multiple transaction boundaries, or to pass the transaction context explicitly across method boundaries.

dataSource.transaction() vs QueryRunner

When to use each approach:

1
dataSource.transaction() — preferred for most cases; handles commit and rollback automatically.
2

What are the two main ways to run a database transaction in TypeORM with NestJS?

Difficulty: 5/10

TypeORM transactions, NestJS integration, QueryRunner

Use dataSource.transaction() with a callback for automatic commit and rollback — the recommended approach for most cases. Use QueryRunner for manual control when you need savepoints, multiple transaction boundaries, or to pass the transaction context explicitly across method boundaries.

dataSource.transaction() vs QueryRunner

When to use each approach:

1
dataSource.transaction() — preferred for most cases; handles commit and rollback automatically.
2

What are the two main ways to run a database transaction in TypeORM with NestJS?

Use dataSource.transaction() with a callback for automatic commit and rollback — the recommended approach for most cases. Use QueryRunner for manual control when you need savepoints, multiple transaction boundaries, or to pass the transaction context explicitly across method boundaries.

What are the two main ways to run a database transaction in TypeORM with NestJS?

Use dataSource.transaction() with a callback for automatic commit and rollback — the recommended approach for most cases. Use QueryRunner for manual control when you need savepoints, multiple transaction boundaries, or to pass the transaction context explicitly across method boundaries.

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