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Cast and Clean Data in SQL

MediumSQL · PostgreSQL00:00
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Your question is Cast and Clean Data in SQL. Start with the requirements and the one table on the right.

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Problem

Microsoft Store analysts receive revenue data from multiple reporting systems, so the same value may contain currency symbols, commas, whitespace, or invalid text. Write a PostgreSQL query to prepare the revenue column for analysis.

Requirements

  1. Clean raw_revenue by removing currency symbols, commas, and surrounding whitespace, then cast valid values to NUMERIC(12,2).
  2. Return every sale, using NULL for missing or invalid revenue values, and order the results by sale_id.

Schema

store_sales
ColumnTypeDescription
sale_idPKINTEGERUnique sale identifier
product_nameVARCHAR(100)Microsoft Store product name
raw_revenueVARCHAR(30)Revenue received as unprocessed text
Tablesstore_sales
Your solutionPostgreSQL
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