mysqli_query“INSERT INTO”

Question

我用这个代码，但它这么想的插入我的数据base..please帮我

mysqli_query($link, 
      "INSERT INTO `usertable`(`id`, `username`, `password`) 
      VALUES (NULL,'$username','$password')" 
     ); 

Answer 1

mysqli_query("INSERT INTO `usertable`(`username`, `password`) 
     VALUES ('$username','$password')" 
    ); 

数据库集ID自动递增。

Answer 2

mysqli_query($link, 
      "INSERT INTO `usertable`(`username`, `password`) 
      VALUES ('$username','$password')" 
     ); 

然后运行丢失的详细信息的SQL

ALTER TABLE `usertable` CHANGE `id` `id` INT(11) NOT NULL AUTO_INCREMENT;