Oracle SQL更新查询仅更新值为空的值

本文介绍了Oracle SQL更新查询仅更新值为空的值的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我有以下查询，仅在它们为空时才在其中更新值.

I have the following queries where I am updating values only if they are null.

是否可以将所有这些都放在一个查询中?

Is it possible to put all of these into a single query?

UPDATE test SET test1 = 'hello' WHERE test1 IS NULL

和

UPDATE test SET test2 = 'world' WHERE test2 IS NULL

推荐答案

您可以尝试:

UPDATE test SET test1 = NVL(test1, 'hello'), test2 = NVL(test2, 'world') WHERE test2 IS NULL OR test1 IS NULL;

尽管即使对于实际上未更改的行，它也可能会触发更新触发器.

Though it may fire your update triggers even for the rows that are effectively unchanged.