Tagged articles

Database Constraints

4 articles · Page 1 of 1

Sep 20, 2026 · Backend Development

How to Guarantee Single Order Processing When Payment Callbacks Fire 10 Times

The article explains how to handle duplicate payment callbacks in Spring Boot using database unique constraints, conditional state updates, an outbox pattern for reliable event publishing, and downstream idempotency, ensuring orders are processed exactly once even if the payment platform sends repeated notifications.

Database ConstraintsIdempotencyOutbox Pattern

0 likes · 17 min read

How to Guarantee Single Order Processing When Payment Callbacks Fire 10 Times

Mike Chen's Internet Architecture

Aug 18, 2026 · Backend Development

How Alipay Ensures Payment Idempotency in High‑Concurrency Systems

The article explains why idempotency is critical for Alipay’s high‑concurrency, high‑reliability payment platform and outlines four key reasons—funds safety, handling network uncertainty, user experience, and distributed architecture—followed by concrete solutions such as unique business identifiers, database unique constraints, state‑machine control, and idempotent API design.

Database ConstraintsIdempotencybackend design

0 likes · 6 min read

How Alipay Ensures Payment Idempotency in High‑Concurrency Systems

Coder Life Journal

Jul 20, 2026 · Backend Development

Redis Distributed Lock with Three Checks: Why Small Projects Should Rethink Its Use

The article analyzes Redis distributed locks—its three‑step verification, the limited guarantees it provides, and why small‑to‑medium projects should often prefer database constraints, idempotency keys, or state machines over adding a lock that introduces extra complexity and maintenance overhead.

Backend DevelopmentDatabase ConstraintsDistributed Lock

0 likes · 10 min read

Redis Distributed Lock with Three Checks: Why Small Projects Should Rethink Its Use

Architecture Digest

Aug 18, 2025 · Backend Development

Why a Username of "null" Breaks Your System and How to Prevent It

The article explains how using the literal string "null" as a username can cause user‑experience glitches, log‑debugging nightmares, database pollution, security risks and automation failures, and provides concrete backend, frontend and database validation techniques to avoid these pitfalls.

Backend DevelopmentDatabase Constraintsnull string

0 likes · 5 min read

Why a Username of "null" Breaks Your System and How to Prevent It