根据同一行的值更新行

Question

我正在尝试使用这样的请求对一行进行非常简单的更新：

UPDATE MY_TABLE 
SET LINE_TX = 1000/(SELECT AMOUNT FROM MY_TABLE WHERE LINE_ID = 1 AND LINE_ORDER = 2)
WHERE LINE_ID = 1 AND LINE_ORDER = 2;

有没有办法只用 一个 where 子句？

Answer 1

只需引用该列：

UPDATE MY_TABLE 
    SET LINE_TX = 1000 / AMOUNT
    WHERE LINE_ID = 1 AND LINE_ORDER = 2;