如何使用空值更新列
我正在使用 mysql 并且需要使用空值更新列.我已经尝试了很多不同的方法，我得到的最好的方法是一个空字符串.
I am using mysql and need to update a column with a null value. I have tried this many different ways and the best I have gotten is an empty string.
是否有特殊的语法可以做到这一点?
Is there a special syntax to do this?
推荐答案
无特殊语法:
CREATE TABLE your_table (some_id int, your_column varchar(100));
INSERT INTO your_table VALUES (1, 'Hello');
UPDATE your_table
SET your_column = NULL
WHERE some_id = 1;
SELECT * FROM your_table WHERE your_column IS NULL;
+---------+-------------+
| some_id | your_column |
+---------+-------------+
| 1 | NULL |
+---------+-------------+
1 row in set (0.00 sec)
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