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Write SQL for Business Tables
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Write SQL for Business Tables

MediumSQL · PostgreSQL

Problem

They gave you input and output tables and asked you to write a SQL query.

Use the provided customers and trips tables to return one row for every customer, summarizing only completed trips. Assign an activity level based on the customer's completed trip count.

Output

  1. Columns: customer_id, customer_name, completed_trip_count, total_completed_fare, and activity_level
  2. Include customers with no completed trips, using zero totals and None as their activity level
  3. Sort by total_completed_fare descending, then customer_id ascending

Schema

customers
ColumnTypeDescription
customer_idPKINTUnique customer identifier
customer_nameVARCHAR(100)Customer display name
trips
ColumnTypeDescription
trip_idPKINTUnique trip identifier
customer_idINTCustomer associated with the trip
statusVARCHAR(20)Trip status
fare_amountNUMERIC(10,2)Fare charged for the trip
Tablescustomerstrips
Interviewer

Your question is Write SQL for Business Tables. Start with the requirements and the two tables in the Question tab.

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