Cleaning a Messy Dataset | Dataford Interview Questions

Given this dataset, how would you clean it?

Write a SQL query that returns a cleaned version of the data with standardized text values, trimmed whitespace, and invalid or missing fields handled consistently.

Output

One row per source record
Columns: cleaned values for each field in the dataset, using clear aliases
Keep all source rows, but normalize obvious data quality issues
Sort by the primary key in ascending order

Schema

raw_orders

Column	Type	Description
idPK	INT	Source record identifier
customer_name	VARCHAR(255)	Customer name with possible whitespace or casing issues
email	VARCHAR(255)	Customer email with possible blanks or casing issues
status	VARCHAR(50)	Order status that may be blank or inconsistent
amount	NUMERIC(10,2)	Order amount that may contain invalid values
order_date	DATE	Order date that may be missing

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