# Install the "Database Indexing & Query Tuning" skill

You are installing an AgenticMarket skill into this workspace. Follow these steps exactly.

## 1. Detect your environment and choose the destination file
- Andromity: `.andromity/skills/database-indexing-optimization/SKILL.md` (or user scope `~/.andromity/skills/database-indexing-optimization/SKILL.md`)
- Antigravity / Gemini CLI: `.agent/skills/database-indexing-optimization/SKILL.md`
- Cursor: `.cursor/rules/database-indexing-optimization.mdc`
- Claude Code: append to `CLAUDE.md` (or `.claude/skills/database-indexing-optimization.md`)
- Windsurf: append to `.windsurfrules`
- Cline / Roo Code: `.clinerules/database-indexing-optimization.md`
- GitHub Copilot: append to `.github/copilot-instructions.md`
- ChatGPT / web only: paste the content into Custom Instructions
- Any other agent: save to `.agent/skills/database-indexing-optimization/SKILL.md`

## 2. Create the destination file
- Preserve every existing file and configuration entry.
- Create parent folders as needed.
- Never overwrite unrelated content.

## 3. Write exactly this content

```markdown
---
name: database-indexing-optimization
description: "Analyze SQL EXPLAIN plans, design composite indexes, eliminate table scans, and optimize slow database queries."
author: community
license: mit
version: 1.0.0
---
# SQL Query Tuning & Indexing

Principles of index design:
- Order composite index columns by equality filters first, then range filters (`where status = 'active' and created_at > ...`).
- Ensure indexes cover selected columns when feasible to enable index-only scans.
- Run `EXPLAIN QUERY PLAN` before deploying new query patterns.
```

## 4. Verify
- Confirm the file exists and is readable.
- Report the destination path and confirm the "Database Indexing & Query Tuning" skill is installed and active.

Skill metadata:
- Slug: database-indexing-optimization
- Category: development
- License: mit
- Source: AgenticMarket