mysql - 重复键 MYSQL 不工作

Question

我已经阅读了几十篇文章，但我不知道我无法理解。我希望这个线程不会重复。

所以，我尝试插入数据但是最后如果数据已经在表上了。如果不是，它将更新该值，然后将数据插入表中。我读过我必须使用

INSERT INTO table() VALUES() ON DUPLICATE KEY data1='$data1', data2='$data2'

然后，这是我的代码

$sql = "INSERT INTO niche_new(gamename,domain,url,type,date) VALUES('$gamename','$websiteurl','$url','download','$waktu') ON DUPLICATE KEY UPDATE domain='$websiteurl',url='$url'";
$process = $conn->query($sql) or die("Error: ".$conn->error);

In the end of the query.

The data won't be updated, but it is inserted. It makes my table has lots of duplicate data.

我非常感谢任何答案。谢谢:)

Note: It was a great mistake. I forgot to set unique key on my table. To whom who want to use ON DUPLICATE KEY, make sure you set UNIQUE KEY by picking which ROW as your parameter. It works now.

Answer 1

如果插入重复数据，很可能您插入的列都没有 UNIQUE 或 PRIMARY KEY 修饰符。