A FastAPI web application that leverages a Large Language Model (LLM) to interact with a SQL database using natural language queries. The application supports both direct querying and Retrieval-Augmented Generation (RAG) for enhanced responses.
sqlagent_web/
├── app/
│ ├── __init__.py # Module initialization (exports app)
│ ├── config.py # Configuration management with Pydantic Settings
│ ├── main.py # FastAPI app + CORS configuration
│ ├── routes.py # API endpoints (query, stream, static)
│ ├── agent_service.py # SQLAgentService class
│ ├── parsers.py # Data extraction & transformation
│ └── debug_utils.py # Agent reasoning timeline display
├── data/ # Generated files (schema descriptions, FAISS index)
├── scripts/
│ ├── init_schema.py # Generate schema descriptions using LLM
│ └── build_index.py # Build FAISS vector index for RAG
├── .env # Environment variables (not in version control)
├── .gitignore # Git ignore rules (includes .env)
├── app.py # Entry point (imports from app.main)
├── index.html # Frontend SPA (no build process required)
├── Chinook.db # SQLite sample database (read-only)
├── pyproject.toml # Python 3.12 + dependencies (includes pydantic-settings)
└── uv.lock # Locked dependency versions
- Python 3.12+
uvpackage manager- AWS Bedrock access with Claude Sonnet 4.5
# Install dependencies
uv sync
# Initialize schema descriptions (required for RAG)
uv run python scripts/init_schema.py
# Build FAISS vector index (required for RAG)
uv run python scripts/build_index.py# Development mode (auto-reload)
uvicorn app:app --reload --host 0.0.0.0 --port 8000
# Or run directly
python app.pyAccess at: http://localhost:8000
Show me all artists
List customers from USA
What are the top 5 albums by total sales?
Which tracks are longer than 5 minutes?
Show total sales by country
All settings via .env file:
| Variable | Description | Default |
|---|---|---|
DB_URI | Database connection string | sqlite:///./Chinook.db |
MODEL_NAME | LLM model identifier | bedrock:us.anthropic.claude-sonnet-4-5-20250929-v1:0 |
TOP_K | Default result limit | 20 |
RAG_TOP_K | RAG retrieval limit | 5 |
RECURSION_LIMIT | Max agent iterations | 15 |