Vibe codingHardvc-g108

Subject Ai code reviewLevel Senior–Staff~18 minCommon in Databases & SQL interviewsIndustries Software development

Question

An AI agent wrote this Java service method to create an order, charge the card, and send a confirmation email — all wrapped in one transaction for 'consistency'. Under load, the team sees database connection-pool exhaustion and occasional orders with no payment.

java

1@Transactional2public Order placeOrder(Cart cart) {3    Order order = orderRepo.save(new Order(cart));4    PaymentResult pr = paymentGateway.charge(cart.total()); // external HTTP, ~800ms5    order.setPaymentId(pr.getId());6    emailService.sendConfirmation(order);                   // external HTTP, ~400ms7    return orderRepo.save(order);8}

What's wrong with the transaction boundary, and how should this be structured?

What a strong answer looks like

Treat the AI’s output as a draft to verify, not an answer to trust. Name the specific flaw and the input that triggers it, say how you’d catch it — tests, edge cases, reading critically — and how you’d re-prompt or decompose to get it right.

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Describe your solution

Vibe coding: describe the solution in plain language (or narrate it) and the coach grades your approach. Generating runnable code from your description is coming next.

Run or narrate your approach, then ask the coach.