尝试使 PHP 检查数据插入中的重复项 - Trying to make PHP check for duplicates in data insert

Trying to make PHP check for duplicates in data insert

本文关键字：插入数据 PHP 检查 | 更新日期: 2023-09-27

mysql_connect("host","admin","password");//database connection
mysql_select_db("dbname");

$order="INSERT INTO members (username, password) VALUES ('$_POST[username]','$_POST[password]')";

$doopquery = mysql_query("SELECT username FROM members WHERE username='$_POST[username]' ")
if ($doopquery) {
    echo("Username Taken");
} else {
    $result = mysql_query($order);
    echo("Account Registered");
}

？>'

到目前为止，我的数据库连接很好，当我到达$doop

这样做：

$username = mysql_real_escape_string($_POST['username']);
$password = mysql_real_escape_string($_POST['password']);
$query = "SELECT username FROM members WHERE username='{$username}'";
$result = mysql_query($query);
if(mysql_num_rows($result) > 0) {
  echo "Username Already Taken!";
}else{
  $query = "INSERT INTO members (username, password) VALUES ('{$username}','{$password}')";
  if(mysql_query($query)) {
    echo "Account Registered!";
  }else{
    echo "Account Register Failed!";
  }
}

$username=mysql_real_escape_string($_POST['username']);
$doopquery = mysql_query("SELECT username FROM members WHERE username='$username' ");
if(mysql_num_rows($doopquery)==0){
     //username not found
}
else{
      //username already exists
 }

用户名周围缺少 '

缺少 ; 在$doopquery末尾