Pulse
ae39e45460
NOVAS SKILLS: - next-best-practices v0.1.0 (CLEAN) — Next.js App Router, RSC, caching, data - nextjs-patterns v1.0.0 (CLEAN) — Next.js 15: Server Actions, route handlers - vite v1.0.0 (CLEAN) — env vars, aliases, proxy, CJS compat - uncle-bob v1.0.0 (CLEAN) — Clean Code, SOLID, Clean Architecture - clean-code-review v1.0.0 (CLEAN) — naming, guard clauses, anti-patterns, refactoring - vue v1.0.0 (CLEAN) — Vue framework - vue-composition-api-best-practices v1.0.0 (CLEAN) — composables, Pinia, reactivity BIBLIOTECA INTELIGENTE libs/ (10 dominios, 11 arquivos): - typescript/ — TS safe + generics gotchas - react/ — Next.js App Router + Vite config - vue/ — Composition API + Pinia - linux/ — System diagnostic cheatsheet - database/ — PostgreSQL + MySQL patterns - browser/ — Chromium CLI + E2E testing - security/ — SAST audit (OWASP Top 10) - best-practices/ — Clean Code + SOLID + Clean Architecture - deploy/ — Docker multi-stack + OpenClaw ops - + INDEX.md como guia de navegacao .learnings/ — LRN-20260519-003 criado (biblioteca compartilhada)
2.1 KiB
2.1 KiB
MySQL — Patterns e Anti-patterns
Conexão | Schemas | JSON | InnoDB | Otimização
Comandos Rápidos
mysql -h localhost -u root -p mydb
mysql -h host -u user -p -e "SELECT NOW();" mydb
mysql -h host -u user -p mydb < migration.sql
Schema Design
CREATE TABLE users (
id BIGINT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
email VARCHAR(255) NOT NULL UNIQUE,
name VARCHAR(255) NOT NULL,
created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
SEMPRE
ENGINE=InnoDB— transações, FK, row-level locking.utf8mb4— suporta emoji e acentos completos.
JSON Ops
CREATE TABLE orders (
id BIGINT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
metadata JSON,
FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
);
SELECT * FROM orders WHERE JSON_EXTRACT(metadata, '$.source') = 'web';
-- Shorthand (MySQL 8+):
SELECT * FROM orders WHERE metadata->>'$.source' = 'web';
Indexes
-- Index composto
CREATE INDEX idx_orders_user_id ON orders(user_id);
-- Índice parcial (simulado com generated column + índice)
ALTER TABLE orders ADD COLUMN is_active TINYINT(1)
GENERATED ALWAYS AS (status != 'cancelled') STORED;
CREATE INDEX idx_orders_active ON orders(is_active);
Joins e Agregações
SELECT u.name, o.total, o.status
FROM users u
INNER JOIN orders o ON o.user_id = u.id
WHERE o.created_at > '2026-01-01'
ORDER BY o.total DESC
LIMIT 10;
SELECT status, COUNT(*) AS cnt, SUM(total) AS revenue
FROM orders GROUP BY status HAVING cnt > 5;
Diferenças principais vs PostgreSQL
| Aspecto | MySQL | PostgreSQL |
|---|---|---|
| Auto-increment | AUTO_INCREMENT |
SERIAL / IDENTITY |
| UUID padrão | Requer plugin (não padrão) | uuid-ossp built-in |
| JSON | JSON type (baixa performance em queries) |
JSONB indexável |
| CTEs | Suportado (MySQL 8+) | Nativo desde sempre |
| Window Functions | MySQL 8+ | Nativo |
| Transactions | InnoDB obrigatório | Sempre |
| Null-safe join | <=> (spaceship operator) |
IS NOT DISTINCT FROM |