database-plan

A guide to designing databases, including their tables or collections, relationships, indexes, partitions, and storage approach.

In plain words
What is it for?
Use it to choose SQL, NoSQL, or time-series storage; design schemas and diagrams; and plan indexes, partitioning, or sharding.
Why use it?
It helps avoid duplicated data, unsuitable database choices, slow queries, and indexes that make updates more expensive.

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/dongduong2001/pudo-code-system/database
Any agent
npx skills add DongDuong2001/pudo-code-system --skill database
Clone the repo
git clone --depth 1 https://github.com/DongDuong2001/pudo-code-system

Made for: Claude Code, Codex.

Per session 12 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 165 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found 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 $0.00012 $0.00165
Opus 5 $0.00006 $0.00082
Sonnet 5 $0.00002 $0.00033
Haiku 4.5 $0.00001 $0.00016

Measured 2d ago against content hash dda80145a861, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

database-plan 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.

skills/plan/database/SKILL.md · 19 lines

What it actually says

Database Planning Skill

This skill is essential when designing data storage solutions and defining schema boundaries.

When to use this skill

  • When determining whether to use SQL vs NoSQL vs Time-Series databases.
  • When designing entity-relationship diagrams (ERD) schemas.
  • When planning indexing, partitioning, or sharding strategies.

Guidelines

  • Normalize data by default to reduce redundancy, but denormalize strategically for read-heavy performance bottlenecks.
  • Plan indexes based on expected query patterns, not just foreign keys. Remember that excessive indexing slows down write operations.
  • Avoid using UUIDs/GUIDs as primary clustered keys in massive tables where sequential inserts are critical for performance, unless mitigated by the DB engine.
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 · 19 lines · 12 tokens per session scan A dda80145a861

Subscribe to this mod's changes

database-plan is a skill published in the GitHub repository DongDuong2001/pudo-code-system (5 stars, last pushed 26d ago), licensed MIT. It adds 12 tokens to every session and 165 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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