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Explain ETL Process
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Explain ETL Process

MediumSQL · PostgreSQL

Problem

Explain the ETL process.

Use the provided staging and reference tables to demonstrate extraction, transformation, validation, and preparation of load-ready rows. Include records marked READY, preserve data-quality issues with an explanatory status, and exclude records that are not ready.

Output

  1. One row per extracted sale, with sale_id, customer_name, sale_date, amount, sale_month, and quality_status.
  2. Include valid, missing-customer, invalid-amount, and negative-amount records. Sort by sale_date, then sale_id.

Schema

staging_sales
ColumnTypeDescription
sale_idPKINTSource sale identifier
customer_idVARCHAR(10)Source customer identifier
sale_dateDATEDate associated with the sale
amount_textVARCHAR(30)Sale amount received as text
source_statusVARCHAR(20)Source processing status
customer_master
ColumnTypeDescription
customer_idPKVARCHAR(10)Reference customer identifier
customer_nameVARCHAR(100)Reference customer name
customer_segmentVARCHAR(30)Customer classification
Tablesstaging_salescustomer_master
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