postgres

A reference guide for PostgreSQL, a database system used to store and query application data. It covers database design, indexing, query patterns, connections, and performance maintenance.

In plain words
What is it for?
Use it when designing PostgreSQL tables, improving queries and indexes, handling large or time-based tables, or checking vacuum and transaction health.
Why use it?
It helps diagnose slow queries and database connection problems while avoiding common design and maintenance mistakes.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/pageai-pro/ralph-loop/postgres
Any agent
npx skills add PageAI-Pro/ralph-loop --skill postgres
Clone the repo
git clone --depth 1 https://github.com/PageAI-Pro/ralph-loop

Made for: Claude Code, Codex.

Per session 26 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,223 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 100% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00026 $0.01223
Opus 5 $0.00013 $0.00611
Sonnet 5 $0.00005 $0.00245
Haiku 4.5 $0.00003 $0.00122

Measured 2d ago against content hash 8a2a182d58ef, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

postgres scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

100% identical to postgres — 3 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.agent/skills/postgres/SKILL.md · 47 lines

How it starts

The opening of the file, as written. The whole thing — 47 lines — stays where its author put it; the contents beside it link to each section on GitHub.

PlanetScale Postgres

Generic Postgres

Topic Reference Use for
Schema Design references/schema-design.md Tables, primary keys, data types, foreign keys
Indexing references/indexing.md Index types, composite indexes, performance
Index Optimization references/index-optimization.md Unused/duplicate index queries, index audit
Partitioning references/partitioning.md Large tables, time-series, data retention
Query Patterns references/query-patterns.md SQL anti-patterns, JOINs, pagination, batch queries
Optimization Checklist references/optimization-checklist.md Pre-optimization audit, cleanup, readiness checks
MVCC and VACUUM references/mvcc-vacuum.md Dead tuples, long transactions, xid wraparound prevention

Read the full file on GitHub · 47 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 47 lines · 26 tokens per session scan A 8a2a182d58ef

Subscribe to this mod's changes

postgres is a skill published in the GitHub repository PageAI-Pro/ralph-loop (294 stars, last pushed 2mo ago), licensed MIT. It adds 26 tokens to every session and 1,223 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to postgres, differing in 3 lines, and is treated as a copy.