DATA:將多列到一個基於價值從一列
+--------+------+------+------+------+
| WEEK_NO| Week1| Week2| Week3|Week4 |
+--------+------+------+------+------+
| 1 | 0.5 | 0.2 | 0.3 |0.4 |
| 2 | 0.5 | 0.2 | 0.3 |0.4 |
| 3 | 0.5 | 0.2 | 0.3 |0.4 |
| 4 | 0.5 | 0.2 | 0.3 |0.4 |
+--------+------+------+------+------+
所需的輸出:
+--------+------+------+------+------+-------------+
| WEEK_NO| Week1| Week2| Week3|Week4 |COLUMN NEEDED|
+--------+------+------+------+------+-------------+
| 1 | 0.5 | 0.2 | 0.3 |0.4 | 0.5 |
| 2 | 0.5 | 0.2 | 0.3 |0.4 | 0.2 |
| 3 | 0.5 | 0.2 | 0.3 |0.4 | 0.3 |
| 4 | 0.5 | 0.2 | 0.3 |0.4 | 0.4 |
+--------+------+------+------+------+-------------+
它會以不愉快的病例陳述結束......例如:'CASE WHEN WEEK_NO = 1 then WEEK1' ..但爲什麼數據會以這種方式保存?也許是一個測驗! –
這聽起來好像你應該考慮規範你的數據模型。 –
@a_horse_with_no_name \t 我同意你的觀點,但不知何故,數據是在上述結構,不能改變在源 –