checking an id

[firelior]

Hi,
I got a problem, I want to check the id that im sending via $_GET
and I want to check if it exist
this is my code:
[code] function check_id($id){
$sql="select * from ".$this->table." where id= ".$id;
if(mysql_query($sql,$this->link)){
if($row=mysql_num_rows($sql)==1){
return true;
}
return false;
}
return false;
}[/code]
please help thanks

[AdRock]

what error are you getting?

[firelior]

I am getting this error:
[code]Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in[/code]
and also, it doesn't check if the id exists:|

[firelior]

never mind fixed the problem..here is the fixed:
[code] function check_id($id){
$sql="select * from ".$this->table." where id= ".$id;
$result=mysql_query($sql);
while($row=mysql_fetch_object($result)){
if($row->id==$id){
return true;
}
return false;
}
return false;
}[/code]

[trq]

A bit inificient. Try...

[code=php:0]
function check_id($id) {
    $sql = "SELECT id FROM $this->table WHERE id=$id";
    if ($result = mysql_query($sql)) {
        if (mysql_num_rows($result)) {
            return true;
        }
    }
    return false;
}
[/code]