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Compute seller counts and vehicle share

This question evaluates data manipulation and analytical SQL competencies such as joining tables, aggregating and deduplicating interaction counts, applying date-window filters, and computing category-level percentage metrics.

You are given two tables:

  1. listing_interactions

    • buyer_id BIGINT
    • seller_id BIGINT
    • event_date DATE
    • product_id BIGINT
    • listing_interactions INT — number of buyer-seller interactions for that product on that date
  2. dim_all_products

    • product_id BIGINT
    • category STRING
    • snapshot_date DATE
    • create_date DATE
    • country STRING

Assumptions:

  • Join the tables on product_id.
  • All dates are stored in UTC.
  • Unless otherwise specified, use all available data.
  • For Question 1, define a product as having multiple interactions if the total listing_interactions summed across all rows for the same (seller_id, product_id) is greater than 1.
  • For Question 2, define newly created listings in the US as products with country = 'US' and create_date in the last 7 calendar days, inclusive of CURRENT_DATE.
  • For Question 2, the numerator and denominator should both use SUM(listing_interactions).

Write SQL for the following two tasks:

  1. How many sellers have more than 3 distinct products that each have multiple interactions?

    • Return one row with column: seller_count
  2. Among newly created US listings from the last 7 days, what percentage of total listing interactions comes from the vehicle category?

    • Return one row with column: vehicle_interaction_pct
    • Express the result as a percentage from 0 to 100.

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