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Validate Monthly Revenue Data Quality

MediumSQL · PostgreSQL00:00
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Your question is Validate Monthly Revenue Data Quality. Start with the requirements and the four tables on the right.

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Problem

Write a PostgreSQL query that summarizes monthly shipped revenue quality for Literati book clubs in Q1 2024. The source data is messy: some order lines are duplicated, some prices or quantities are null, some orders are canceled, and some clubs are not active.

Your output should show the shipment month, the number of distinct shipped orders, how many of those orders had data issues, and cleaned revenue after deduplicating order lines and treating null amounts as 0.

Schema

ColumnTypeDescription
club_id
club_name
status
ColumnTypeDescription
order_id
club_id
order_date
order_status
ColumnTypeDescription
order_item_id
order_id
book_id
quantity
unit_price
line_updated_at
ColumnTypeDescription
shipment_id
order_id
shipped_at
shipment_status
Tablesclubsordersorder_itemsshipments
Your solutionPostgreSQL
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