警告：mysql_num_rows（）期望参数1是资源，在[重复]中给出布尔值

Question

Possible Duplicate:
mysql_fetch_array() expects parameter 1 to be resource, boolean given in select

if (isset($_GET['uid']) && !empty($_GET['uid'])) {
$id = $_GET['uid'];
$sql = "SELECT * FROM `apps` WHERE `id` = ". mysql_real_escape_string($id) ." LIMIT 1";
    if ($result = mysql_query($sql)) {
    if (mysql_num_rows($result) == 1) {
    while($row = mysql_fetch_assoc($result)){
    $username = $row["MCName"];
    echo'

    //Here is a ton of rows and some html.

    ';
    }
    $sql = "SELECT * FROM `apps` WHERE `MCName` = ". $username;
    $result = mysql_query($sql);
    $rows = mysql_num_rows($result);


    }else {
         die('Record not found.');
    }
}
}

Ive tried everything, it keeps failing. I'm not really master of SQL nor PHP. I want to count how many rows there is with the "MCName" I'm not sure if I could do it in the first SQL query. Also, the error appears on line 44, aka the line which does mysql_num_rows. The DB is connected earlier on the script.

Sorry if this is a really dumb question, believe me. I searched for a hour or so for a fix ^^

Answer 1

Your second query has an SQL syntax error:

 $sql = "SELECT * FROM `apps` WHERE `MCName` = ". $username;

The $username variable needs to be wrapped in quotes. Try updating to the following to fix:

 $sql = "SELECT * FROM `apps` WHERE `MCName` = '". $username . "'";