The document describes Nile, an e-commerce sales analytics tool that can record historical sales data, track daily/monthly sales volumes by category, compare month-to-month product revenues, and view product popularity by location in real-time. It uses Kafka to ingest order and product catalog data, HBase for the speed layer, and Hive for batch processing to join orders with products and flatten many-to-many category relationships. The tool precomputes views in HBase to reduce hotspotting and allow querying sales by product and date.