DataLens — Intelligent Data Dictionary Agent

DataLens is a full-stack AI-powered data dictionary agent that connects to any database (SQLite, Snowflake, PostgreSQL) and automatically generates living, enriched documentation — with zero manual effort.

🔍 What it does:
- Auto-extracts complete schema: tables, columns, foreign keys, indexes
- Runs quality analysis grading every table A+ to F across completeness, uniqueness, and freshness
- AI enrichment via Groq (Llama 3.3 70B) writes business-ready descriptions, domain tags, and usage recommendations for every table and column
- Interactive D3 force-directed lineage graph visualises all FK relationships
- Natural language AI Chat — ask questions in plain English, get SQL + answers instantly
- One-click Query Runner executes AI-generated SQL against real data
- ⌘K semantic search finds any table or column by business meaning
- Exports a complete data dictionary as Markdown or JSON

🛠 Built with: FastAPI · React · D3.js · Groq API · SQLite/Snowflake/PostgreSQL
📊 Demo dataset: Olist Brazilian E-Commerce (9 tables, 569,774 rows) — Quality Score 97/100, Grade A+, fully enriched in under 2 minutes on free-tier AI