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Resolve a missing value using evidence

Data preparation practice · Use the messy source and independent clean control. Corrections belong in a derived output and a change log.

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Your task

R05 has a blank status in the messy file. Should you fill every blank with completed? Describe the risk of an automatic correction.

Hint

Distinguish formatting fixes from changes in business meaning. Specify what evidence authorizes each correction.

Worked solution

No. Flag R05 for review; the independent clean control file identifies it as completed. Record field=status, old=blank, new=completed, source=clean control, reason and reviewer/date. If no control exists, keep it unresolved and disclose exclusion.

What to hand over

Provide raw source fingerprint, old/new values, rule, evidence, affected row IDs and validation totals. A clean-looking table alone is insufficient.

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