عرض عملي: نسخ القراءة وخطأ القراءة القديمة الذي تسببه

خطوة بخطوة

1. Add a replica and route reads to it.
2. Place an order, then immediately load "my orders"; the order is missing.
3. Planned mistake: blame the cache. Fix: confirm replica lag in metrics; the read went to the replica.
4. Implement read-your-writes: route recent writers to the primary or wait for the replica's position.
5. Add lag monitoring and a fallback threshold.
6. Add a test that fails when the stale read returns.