sql

SQL database queries, joins, aggregations, subqueries, and optimization. Use for .sql files and database operations.

7 stars

byG1Joshi

View on GitHub Installation ↓

Best use case

sql is best used when you need a repeatable AI agent workflow instead of a one-off prompt.

SQL database queries, joins, aggregations, subqueries, and optimization. Use for .sql files and database operations.

Teams using sql should expect a more consistent output, faster repeated execution, less prompt rewriting.

When to use this skill

You want a reusable workflow that can be run more than once with consistent structure.

When not to use this skill

You only need a quick one-off answer and do not need a reusable workflow.
You cannot install or maintain the underlying files, dependencies, or repository context.

Installation

Claude Code / Cursor / Codex

$curl -o ~/.claude/skills/sql/SKILL.md --create-dirs "https://raw.githubusercontent.com/G1Joshi/Agent-Skills/main/skills/languages/sql/SKILL.md"

Manual Installation

Download SKILL.md from GitHub
Place it in .claude/skills/sql/SKILL.md inside your project
Restart your AI agent — it will auto-discover the skill

How sql Compares

Feature / Agent	sql	Standard Approach
Platform Support	Not specified	Limited / Varies
Context Awareness	High	Baseline
Installation Complexity	Unknown	N/A

Frequently Asked Questions

What does this skill do?

SQL database queries, joins, aggregations, subqueries, and optimization. Use for .sql files and database operations.

Where can I find the source code?

You can find the source code on GitHub using the link provided at the top of the page.

SKILL.md Source

# SQL

Standard language for storing, manipulating and retrieving data in databases.

## When to Use

- Relational data modeling
- Complex queries and aggregations
- Data integrity enforcement (ACID)
- Standardized data access

## Quick Start

```sql
-- Create Table
CREATE TABLE users (
    id SERIAL PRIMARY KEY,
    name VARCHAR(100),
    email VARCHAR(100) UNIQUE
);

-- Insert Data
INSERT INTO users (name, email) VALUES ('Alice', 'alice@example.com');

-- Query Data
SELECT * FROM users WHERE name = 'Alice';
```

## Core Concepts

### DDL (Data Definition Language)

Commands to define database schemas (CREATE, ALTER, DROP).

### DML (Data Manipulation Language)

Commands to manipulate data (SELECT, INSERT, UPDATE, DELETE).

### Joins

Combining rows from two or more tables based on a related column.

- **INNER JOIN**: Matches in both tables.
- **LEFT JOIN**: All from left, matches from right.

## Best Practices

**Do**:

- Use parameterized queries (prevent SQL Injection)
- Index columns used in WHERE and JOIN clauses
- Use transactions for atomic operations

**Don't**:

- Use `SELECT *` in production (fetch only what you need)
- Store logic in triggers if possible (hard to debug)
- Ignore execution plans for slow queries

## References

- [PostgreSQL Documentation](https://www.postgresql.org/docs/)