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SQL Problem Solving
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SQL Problem Solving

MediumSQL · PostgreSQL

Problem

Describe how you would write SQL to solve a data problem from scratch.

Use the provided customers and orders tables. Return customers with at least two completed orders, including their order count, total completed order value, latest completed order date, and spending classification.

Output

  1. One row per qualifying customer with columns customer_id, customer_name, order_count, total_spent, latest_order_date, and spending_band.
  2. Exclude customers with fewer than two completed orders.
  3. Sort by total_spent descending, then customer_id ascending.

Schema

customers
ColumnTypeDescription
customer_idPKINTUnique customer identifier
customer_nameVARCHAR(100)Customer's full name
emailVARCHAR(255)Customer email address
orders
ColumnTypeDescription
order_idPKINTUnique order identifier
customer_idINTCustomer who placed the order
statusVARCHAR(30)Order processing status
order_amountNUMERIC(10,2)Order monetary value
order_dateDATEDate the order was placed
Tablescustomersorders
Interviewer

Your question is SQL Problem Solving. Start with the requirements and the two tables in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

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