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Top Merchants Query
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Top Merchants Query

EasySQL · PostgreSQL

Problem

Write a query to find the top 10 merchants by transaction volume.

Use the available merchant and transaction records. Treat transaction volume as the count of transaction records associated with each merchant.

Output

  1. Return one row per merchant with at least one transaction.
  2. Include merchant_id, merchant_name, and transaction_volume.
  3. Order by transaction volume descending, then merchant ID ascending for ties, and return at most 10 rows.

Schema

merchants
ColumnTypeDescription
merchant_idPKINTUnique merchant identifier
merchant_nameVARCHAR(150)Merchant display name
transactions
ColumnTypeDescription
transaction_idPKINTUnique transaction identifier
merchant_idINTMerchant associated with the transaction
Tablesmerchantstransactions
Interviewer

Your question is Top Merchants Query. Start with the requirements and the two tables in the Question tab.

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CodePostgreSQL
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