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Shipping Confirmation Missing Orders
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Shipping Confirmation Missing Orders

MediumSQL · PostgreSQL

Problem

Given two tables, write a query to identify customers who placed an order but never received a shipping confirmation for Bed Bath & Beyond orders.

Return each customer who has at least one order without a matching shipping confirmation. A customer should appear once even if they placed multiple orders.

Output

  1. Columns: customer_id, customer_name
  2. One row per qualifying customer
  3. Sort by customer_id ascending

Schema

orders
ColumnTypeDescription
order_idPKINTUnique identifier for the order
customer_idINTIdentifier of the customer who placed the order
customer_nameVARCHAR(120)Customer name associated with the order
order_dateDATEDate the order was placed
shipping_confirmations
ColumnTypeDescription
confirmation_idPKINTUnique identifier for the shipping confirmation
order_idINTOrder associated with the shipping confirmation
confirmed_atTIMESTAMPTimestamp when the shipping confirmation was received
Tablesordersshipping_confirmations
Interviewer

Your question is Shipping Confirmation Missing Orders. Start with the requirements and the two tables in the Question tab.

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