Unpivot survey answers without inventing scores · SQL
Task: the rules
Input survey(respondent, q1, q2, q3) — text. respondent is unique. Each answer is a whole number 1–5 or missing. Rules Reshape to one row per respondent and question: question is the column name (q1, q2 or q3), score is the answer as a whole number. An unanswered question produces no row. It is not a score of 0 and it is not an error. Output (row order does not matter) clean(respondent text, question text, score int64)
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| # | respondentstring | q1string | q2string | q3string |
|---|---|---|---|---|
| 1 | r344 | 2 | 1 | missing |
| 2 | r390 | missing | missing | missing |
| 3 | r342 | 5 | 3 | missing |
| 4 | r340 | missing | 1 | 2 |
| 5 | r341 | 5 | missing | 1 |
| 6 | r343 | 3 | 2 | 4 |
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