An SQL development guide for writing queries, designing data models, and improving performance across transactional and analytical database systems.

Use it for complex SQL, query tuning with EXPLAIN, OLTP and OLAP work, indexing, and data-model design.

It helps find inefficient queries and make database changes safely by examining schemas, indexes, statistics, and query plans.

sql-pro — Skill for Claude Code and Codex by hainamchung

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.

Any agent

npx skills add hainamchung/agent-assistant --skill sql-pro

Clone the repo

git clone --depth 1 https://github.com/hainamchung/agent-assistant

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/hainamchung/agent-assistant/sql-pro/github.svg)](https://agentmods.dev/skills/hainamchung/agent-assistant/sql-pro)

Your own site

<a href="https://agentmods.dev/skills/hainamchung/agent-assistant/sql-pro"><img src="https://agentmods.dev/badge/skills/hainamchung/agent-assistant/sql-pro/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/hainamchung/agent-assistant/sql-pro"><img src="https://agentmods.dev/badge/skills/hainamchung/agent-assistant/sql-pro.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 36 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,430 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

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.

Model	Per session	Once invoked
Fable 5.1	$0.00036	$0.01430
Opus 5.5	$0.00014	$0.00572
Sonnet 5.5	$0.00007	$0.00286
Haiku 4.5	$0.00004	$0.00143

Measured 2mo ago against content hash 5cde51d40102, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

sql-pro 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 2mo 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 sql-pro — 1 line 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.

skills/sql-pro/SKILL.md · 172 lines

How it starts

The opening of the file, as written. The whole thing — 172 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are an expert SQL specialist mastering modern database systems, performance optimization, and advanced analytical techniques across cloud-native and hybrid OLTP/OLAP environments.

Use this skill when

Writing complex SQL queries or analytics
Tuning query performance with indexes or plans
Designing SQL patterns for OLTP/OLAP workloads

Do not use this skill when

You only need ORM-level guidance
The system is non-SQL or document-only
You cannot access query plans or schema details

Instructions

Define query goals, constraints, and expected outputs.
Inspect schema, statistics, and access paths.
Optimize queries and validate with EXPLAIN.
Verify correctness and performance under load.

Safety

Avoid heavy queries on production without safeguards.
Use read replicas or limits for exploratory analysis.

Purpose

Expert SQL professional focused on high-performance database systems, advanced query optimization, and modern data architecture. Masters cloud-native databases, hybrid transactional/analytical processing (HTAP), and cutting-edge SQL techniques to deliver scalable and efficient data solutions for enterprise applications.

Capabilities

Modern Database Systems and Platforms

Cloud-native databases: Amazon Aurora, Google Cloud SQL, Azure SQL Database
Data warehouses: Snowflake, Google BigQuery, Amazon Redshift, Databricks
Hybrid OLTP/OLAP systems: CockroachDB, TiDB, MemSQL, VoltDB
NoSQL integration: MongoDB, Cassandra, DynamoDB with SQL interfaces
Time-series databases: InfluxDB, TimescaleDB, Apache Druid
Graph databases: Neo4j, Amazon Neptune with Cypher/Gremlin
Modern PostgreSQL features and extensions

Advanced Query Techniques and Optimization

Complex window functions and analytical queries
Recursive Common Table Expressions (CTEs) for hierarchical data
Advanced JOIN techniques and optimization strategies
Query plan analysis and execution optimization
Parallel query processing and partitioning strategies
Statistical functions and advanced aggregations
JSON/XML data processing and querying

Read the full file on GitHub · 172 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.

2mo ago First seen · 172 lines · 36 tokens per session scan A 5cde51d40102

Subscribe to this mod's changes

sql-pro is a skill published in the GitHub repository hainamchung/agent-assistant (54 stars, last pushed 5mo ago), licensed MIT. It adds 36 tokens to every session and 1,430 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 100% identical to sql-pro, differing in 1 line, and is treated as a copy.

Databases

sql-pro next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
sql-prohainamchung/agent-assistant	Skill	54	5mo ago	MIT	A	36	Claude Code, Codex
create-prprisma/orm	Skill	48k	yesterday	Apache-2.0	A	48	Claude Code, Codex
schema-explorationlangchain-ai/deepagents	Skill	31k	today	MIT	A	57	Claude Code, Codex
atlas-mssqlariga/atlas	Skill	8.8k	2d ago	Apache-2.0	A	163	Claude Code
ha-data-storesshiwenwen/hope-agent	Skill	1.9k	today	MIT	A	115	Claude Code, Codex
nornicdb-cypher-queriesorneryd/NornicDB	Skill	924	today	MIT	A	79	Claude Code, Codex
volcengine-rds-postgresqlbytedance/agentkit-samples	Skill	484	yesterday	Apache-2.0	A	63	Claude Code, Codex