mysql - 按 DESC 顺序更新列，直到出现值

Question

有没有办法按降序更新 NULL 列的值，直到出现一个值？

所以基本上

UPDATE myTable SET myColumn = "val" WHERE myColumn IS NULL ORDER BY id DESC 
(Until myColumn has a non-NULL value, then stop updating).

Answer 1

试试这个:

UPDATE myTable SET myColumn = "val"
WHERE id > (SELECT id FROM myTable
            WHERE myColumn IS NOT NULL ORDER BY id DESC LIMIT 1)