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Top 10 Customers SQL

EasySQL · PostgreSQL00:00
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Your question is Top 10 Customers SQL. Start with the requirements and the one table on the right.

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Problem

Healthfirst Marketplace tracks member purchases in a transaction ledger. The analytics team needs the ten customer accounts with the highest cumulative purchase value.

Write a PostgreSQL query against member_purchase_transactions to return the top 10 customers by total purchase amount.

Requirements

  1. Group all transactions by customer_name and calculate each customer's total purchase amount.
  2. Sort totals from highest to lowest, place NULL totals last, and return only 10 rows. Use customer_name as a secondary ascending sort for deterministic ordering.

Schema

member_purchase_transactions
ColumnTypeDescription
transaction_idPKINTEGERUnique identifier for a marketplace purchase transaction.
customer_nameVARCHAR(100)Name of the Healthfirst Marketplace customer account.
purchase_amountNUMERIC(12,2)Recorded purchase value. NULL represents an unpriced pending adjustment.
purchase_dateDATEDate the transaction was recorded.
Tablesmember_purchase_transactions
Your solutionPostgreSQL
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