Excel的A列是分组，B列是明细。
| A | B | |
| 1 | Group | Name |
| 2 | A | John |
| 3 | A | Joe |
| 4 | A | Ann |
| 5 | A | Susan |
| 6 | A | James |
| 7 | A | Mary |
| 8 | A | L .orraine |
| 9 | B | Joseph |
| 10 | B | Sinead |
| 11 | B | Michelle |
| 12 | B | Breege |
| 13 | B | Tom |
| 14 | B | Francis |
| 15 | B | Conan |
| 16 | B | Cait |
| 17 | B | Ronan |
| 18 | B | Deirdre |
| 19 | B | Aoife |
| 20 | B | Sile |
| 21 | B | Sarah |
| 22 | C | Lisa |
| 23 | C | Micky |
| 24 | C | Pat |
| 25 | D | Miles |
| 26 | D | Olivia |
| 27 | D | Avril |
| 28 | D | Conor |
| 29 | D | Jane |
| 30 | D | Robyn |
| 31 | D | June |
要求从每组中随机选出一行。
| E | F | |
| 1 | Group | Name |
| 2 | A | Mary |
| 3 | B | Sarah |
| 4 | C | Micky |
| 5 | D | Miles |
使用 SPL XLL
=spl("=E(?).sort(rand()).group@1(Group)",A1:B31)
函数 E 将片区解析为表格，sort(rand()) 随机排序，group@1 分组并取每组第 1 条记录。
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