需要帮助修改PHP创建用户代码以编辑用户代码

This is my php code below and I need to write some code for editing the user details, I need to write code and I have done create user but don't know how to, do editing,please help me

// Handle user request
     $create_user =  "INSERT INTO details (username, password, first_name, last_name, gender,email,nationality,ethnicity,address,postcode,tel_number,employment_type,start_of_employment, bio)" . 
    "VALUES ('{$username}', '{$password}', '{$first_name}', '{$last_name}', '{$gender}','{$email}', '{$nationality}','{$ethnicity}','{$address}','{$postcode}','{$tel_number}','{$employment_type}','{$start_of_employment}','{$bio}');";

You want an UPDATE statement, something like this:

UPDATE details SET username = "mynewusername", password = "mynewpassword" WHERE detail_id = 5;

You need to use mysql_real_escape_string() to sanitise your input data or you be open to SQL Injection attacks.

Your code would therefore be something like this:

$edit_user = "UPDATE details SET username = '" . mysql_real_escape_string($username) . "', password = '" . mysql_real_escape_string($password) . "' WHERE detail_id = " . mysql_real_escape_string($detail_id) . ";";

You'll need to expand this to include all your fields.

As another side note, you should probably be using the mysqli_* functions instead of the mysql_* functions, as the latter are deprecated and will be removed from PHP soon.