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SQL Customer-Specific Error Messages
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SQL Customer-Specific Error Messages

MediumSQL · PostgreSQL

Problem

How would you add a customer-specific error message in SQL?

Using the customers and payment_attempts tables, return every failed payment attempt with a message tailored to its error code and customer. Use a generic customer label when no matching customer record or customer name exists.

Output

  1. One row per failed payment attempt, ordered by attempted_at ascending and attempt_id ascending.
  2. Columns: attempt_id, customer_id, customer_name, error_code, and error_message.

Schema

customers
ColumnTypeDescription
customer_idPKINTUnique customer identifier
customer_nameVARCHAR(100)Customer display name
account_statusVARCHAR(20)Current account status
preferred_channelVARCHAR(20)Preferred customer contact channel
payment_attempts
ColumnTypeDescription
attempt_idPKINTUnique payment attempt identifier
customer_idINTCustomer identifier supplied with the payment attempt
attempted_atTIMESTAMPTime of the payment attempt
amountDECIMAL(10,2)Payment amount
statusVARCHAR(20)Payment processing status
error_codeVARCHAR(40)Processing error code
Tablescustomerspayment_attempts
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