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Clean Merchant Transactions for Analysis
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Clean Merchant Transactions for Analysis

HardSQL · PostgreSQL

Problem

You need to clean inconsistent PSCU transaction records and produce a category-level summary. The dataset includes duplicate loads, inconsistent merchant text, mixed status labels, inactive members, and missing references. Return one row per merchant category with valid posted transaction count, distinct active member count, and total posted amount.

Schema

ColumnTypeDescription
member_id
member_name
member_status
ColumnTypeDescription
merchant_id
merchant_name
merchant_category
ColumnTypeDescription
txn_id
member_id
merchant_name_raw
txn_date
amount
txn_status
load_ts
Tablespscu_memberspscu_merchantspscu_transactions
Interviewer

Your question is Clean Merchant Transactions for Analysis. Start with the requirements and the three tables in the Question tab.

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