当值为null或不为null时，MySql在触发器中删除

Question

请问我怎么能在触发这样的东西但没有IF？有可能??

...
IF NEW.value IS NULL THEN
       DELETE FROM table WHERE column IS NULL;
ELSE
       DELETE FROM table WHERE column=NEW.value;
END IF;

当值为null时练习，因此删除列为null的行以及设置值时删除行= column = value 我想在没有IF

的触发器中使用它

Answer 1

您可以在一个声明中执行此操作：

...
DELETE FROM table WHERE column IS NULL OR column=NEW.value;
...

修改

DELETE FROM table WHERE (NEW.value IS NULL AND column IS NULL) OR (NEW.value IS NOT NULL AND column = NEW.value)

Answer 2

我认为如果/ else：

，这将与你的功能完全相同

DELETE FROM table WHERE (NEW.value IS NULL AND column IS NULL) OR (column=NEW.value)