Two same rows = a double vote
When a form sends apple twice from the same person, or you copy a grade row by mistake, totals lie. Remove duplicates leaves the first occurrence and deletes the rest.
The Sorter watches that every vote and every subject is in the table only once — where that makes sense.
Duplicates in the survey
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On
Poznamkymake a test: column AAnswer, rows 2–8,appletwice,rollthree times, the rest a mix. -
Select the whole table including the heading A1:A8. Data → Remove duplicates. Column A ticked. OK.
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Unique answers stay — but vote counts do not appear that way. Remove duplicates deletes rows, it does not add them up. For the summary D:E you still count by hand or with KDYŽ.
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On a survey with names: duplicates by the Nama or ID column — one vote per person. Leave the Answer column — the same person can have only one row.
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Before deleting: a copy of the sheet (right-click → Duplicate sheet). Remove duplicates cannot always be Ctrl+Z reliably after saving.
apple and Apple are not a duplicate for the computer — different text. First unify letter size (lowercase), then remove duplicates. Otherwise you have two “different” apples.
Duplicates vs. the same answer from different people
Remove duplicates on the Answer column deletes the second apple — even when another classmate voted that. So:
- duplicates by ID / name (one row per person), not by the answer;
- or first a summary table with COUNTIF, duplicates only on the raw export according to the teacher’s rules.
What often goes wrong
Remove duplicates without a header. Row 1 Answer gets eaten as data.
Remove duplicates on grades. Two subjects with the same grade 2 are not a duplicate — they are two rows. Do not wipe Znamky by the Grade column.
Relying on remove for totals. You still need a Count table.
🏫 Grade average — do not delete
Sheet Znamky: each subject once. Duplicates would mean two Maths rows — that is a data error, not a normal state. If so, fix by hand, not a bulk delete by grade.
💰 Pocket money — the same day
Two rows Mon — a mistake. Remove the duplicate by the Day column, or merge by hand. One day = one row.
📊 Class survey — one vote
Export from a form: duplicates by email or a number in column B. Then unify answers and add them up into D:E.
🏆 Mini dashboard — clean data
The dashboard counts from sheets without duplicate rows. Before the final hand-in go through the survey once — duplicates gone, summary fits.
Now you 💪
First: test duplicates on Poznamky, remove, count rows before/after.
Second: on the survey (or a copy) — the rule “one row per respondent”. Write on Poznamky which column you deleted by.
Check: You know that remove duplicates ≠ a vote summary. Do not wipe Znamky by grade. A copy before the risk.
What to take from this lesson
- Remove duplicates = unique rows, not a total.
- Unify text, then delete. Duplicates by the right column (ID, day).
- Znamky: one subject = one row.
© 2026 Ing. Martin Polak / AlgoRhino · Ketentuan penggunaan konten