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postgres-patterns
GitHubPostgreSQL最佳实践速查，涵盖索引策略、数据类型选择、RLS配置及性能优化反模式检测，基于Supabase规范。
Trigger Scenarios
编写SQL查询或迁移脚本
设计数据库架构
排查慢查询问题
实施行级安全策略
设置数据库连接池
Install
npx skills add NeverSight/learn-skills.dev --skill postgres-patterns -g -y
SKILL.md
Frontmatter
{
"name": "postgres-patterns",
"description": "PostgreSQL 数据库模式，用于查询优化、架构设计、索引和安全。基于 Supabase 最佳实践。"
}
PostgreSQL 模式 (PostgreSQL Patterns)
PostgreSQL 最佳实践的快速参考。有关详细指导，使用 database-reviewer agent。
何时激活
- 编写 SQL 查询或迁移
- 设计数据库架构
- 排查慢查询
- 实施行级安全 (RLS)
- 设置连接池
快速参考
索引备忘单
| Query Pattern | Index Type | Example |
|---|---|---|
WHERE col = value |
B-tree (default) | CREATE INDEX idx ON t (col) |
WHERE col > value |
B-tree | CREATE INDEX idx ON t (col) |
WHERE a = x AND b > y |
Composite | CREATE INDEX idx ON t (a, b) |
WHERE jsonb @> '{}' |
GIN | CREATE INDEX idx ON t USING gin (col) |
WHERE tsv @@ query |
GIN | CREATE INDEX idx ON t USING gin (col) |
| Time-series ranges | BRIN | CREATE INDEX idx ON t USING brin (col) |
数据类型快速参考
| Use Case | Correct Type | Avoid |
|---|---|---|
| IDs | bigint |
int, random UUID |
| Strings | text |
varchar(255) |
| Timestamps | timestamptz |
timestamp |
| Money | numeric(10,2) |
float |
| Flags | boolean |
varchar, int |
常见模式
组合索引顺序:
--Equality columns first, then range columns
CREATE INDEX idx ON orders (status, created_at);
-- Works for: WHERE status = 'pending' AND created_at > '2024-01-01'
覆盖索引:
CREATE INDEX idx ON users (email) INCLUDE (name, created_at);
-- Avoids table lookup for SELECT email, name, created_at
部分索引:
CREATE INDEX idx ON users (email) WHERE deleted_at IS NULL;
-- Smaller index, only includes active users
RLS 策略 (优化的):
CREATE POLICY policy ON orders
USING ((SELECT auth.uid()) = user_id); -- Wrap in SELECT!
UPSERT:
INSERT INTO settings (user_id, key, value)
VALUES (123, 'theme', 'dark')
ON CONFLICT (user_id, key)
DO UPDATE SET value = EXCLUDED.value;
游标分页:
SELECT * FROM products WHERE id > $last_id ORDER BY id LIMIT 20;
-- O(1) vs OFFSET which is O(n)
队列处理:
UPDATE jobs SET status = 'processing'
WHERE id = (
SELECT id FROM jobs WHERE status = 'pending'
ORDER BY created_at LIMIT 1
FOR UPDATE SKIP LOCKED
) RETURNING *;
反模式检测
-- Find unindexed foreign keys
SELECT conrelid::regclass, a.attname
FROM pg_constraint c
JOIN pg_attribute a ON a.attrelid = c.conrelid AND a.attnum = ANY(c.conkey)
WHERE c.contype = 'f'
AND NOT EXISTS (
SELECT 1 FROM pg_index i
WHERE i.indrelid = c.conrelid AND a.attnum = ANY(i.indkey)
);
-- Find slow queries
SELECT query, mean_exec_time, calls
FROM pg_stat_statements
WHERE mean_exec_time > 100
ORDER BY mean_exec_time DESC;
-- Check table bloat
SELECT relname, n_dead_tup, last_vacuum
FROM pg_stat_user_tables
WHERE n_dead_tup > 1000
ORDER BY n_dead_tup DESC;
配置模板
-- Connection limits (adjust for RAM)
ALTER SYSTEM SET max_connections = 100;
ALTER SYSTEM SET work_mem = '8MB';
-- Timeouts
ALTER SYSTEM SET idle_in_transaction_session_timeout = '30s';
ALTER SYSTEM SET statement_timeout = '30s';
-- Monitoring
CREATE EXTENSION IF NOT EXISTS pg_stat_statements;
-- Security defaults
REVOKE ALL ON SCHEMA public FROM public;
SELECT pg_reload_conf();
相关
- Agent:
database-reviewer- 完整的数据库审查工作流 - Skill:
clickhouse-io- ClickHouse 分析模式 - Skill:
backend-patterns- API 和后端模式
Version History
- e0220ca Current 2026-07-05 22:05
