2025 Completed Sales Customer Segmentation

Explain advanced SQL concepts you would use for data engineering tasks.

Using the provided customers and orders tables, write a query that summarizes completed 2025 sales for every customer, including customers with no qualifying orders. The result should demonstrate sales aggregation, regional ranking, null handling, and customer segmentation.

Output

1. One row per customer with customer_id, customer_name, region, completed_orders, total_completed_sales, region_rank, and sales_segment.
2. Include all customers, rank ties equally within each region, and classify sales as Platinum, Gold, Silver, or Bronze.
3. Order by region, region_rank, and customer_id.

Output details

• Count only orders with status completed.
• Include order dates from 2025-01-01 inclusively through, but excluding, 2026-01-01.
• Use descending total sales for regional ranking, with standard competition ranks that leave gaps after ties.
• Treat missing total sales as 0.00 and count customers without qualifying orders as 0.
• Classify totals using thresholds of 500.00 for Platinum, 200.00 for Gold, and 100.00 for Silver; classify lower totals as Bronze.
• Sort region, region_rank, and customer_id in ascending order.