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Clean data without hiding your decisions
Clean data with a record of what you changed and why.
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Clean data without hiding your decisions
Clean data with a record of what you changed and why.
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Source-based teaching example · Fictional data · Reviewed 2026-10-03. Microsoft Mark · locally synthesized. On a small screen, use fullscreen for diagram details or read the transcript.
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0:00 · What you will learn
Clean data with a record of what you changed and why.
What appears on screen
Clean data with a record of what you changed and why.
0:05 · The idea
Use the supplied key and duplicate rule. Preserve unresolved records. Report how much of the data the result actually covers.
What appears on screen
Use the supplied key and duplicate rule. Preserve unresolved records. Report how much of the data the result actually covers.
0:17 · One useful term
Cleaning log. A record of accepted, changed, excluded and unresolved rows with reasons.
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A record of accepted, changed, excluded and unresolved rows with reasons.
0:27 · A worked example · 1
R1 with amount ten appears twice. R2 has fifteen; R3 is missing its amount. The declared rule treats the identical repeated R1 ID as a duplicate.
What appears on screen
R1 with amount ten appears twice. R2 has fifteen; R3 is missing its amount. The declared rule treats the identical repeated R1 ID as a duplicate.
0:41 · A worked example · 2
The known accepted total is twenty-five.
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The known accepted total is twenty-five.
0:47 · Your turn to think
Does that known total establish the full total including R3? Pause and decide before continuing.
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Does that known total establish the full total including R3? Pause the video if you need more time.
1:04 · Why this answer works
No. R3 remains unresolved. Do not treat a repeated item description as a duplicate ID without a rule.
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No. R3 remains unresolved. Do not treat a repeated item description as a duplicate ID without a rule.
1:15 · Check 1
Use the declared key.
What appears on screen
Use the declared key.
1:19 · Check 2
Keep missing and disputed rows.
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Keep missing and disputed rows.
1:24 · Check 3
State incomplete coverage.
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State incomplete coverage.
1:29 · Now try a different case
Open the lesson and try its different practice case. Use every check in the full task. Watching alone does not mark the lesson complete.
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Open the lesson Try the new case Check and revise The full task and its requirements are in the linked lesson.
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