[RESOLVED] Stuck trying to query my table

conjurer

I am getting very close, I have been able to confirm I connect to the database, been able to confirm that my user name and password are in the "users" table. I come back from that login function returning true

Now when I try to query the other table for data it bombs. Can someone please help me sort where I am screwed up here? I am pretty new to php but am starting to get it. A little help would be deeply appreciated. 😕

The error handler has given me the following errors:

Encountered error: 8 in home/omgma/public_html/Fresh_start/member.php5, line 63: Undefined variable: conn

Encountered error: 2 in /home/omgma/public_html/Fresh_start/member.php5, line 63: mysqli_query() expects parameter 1 to be mysqli, null given

Encountered error: 2 in /home/omgma/public_html/Fresh_start/member.php5, line 64: mysqli_num_rows() expects parameter 1 to be mysqli_result, null given

Line 63 and 64 are from this part:

59  // if logged in run query 
60    $query = "select user_id, last_name, first_name from directory ";
61    echo "<p>Starting query: $query </p>";
62  

63	$result = mysqli_query($conn, $query);
64	$num_results = mysqli_num_rows($result);

My connection functions are as follows:

if ($username && $passwd)
{
  // they have just tried logging in
  login($username, $passwd);
  // if they are in the database register the user id
    $_SESSION['valid_user'] = $username;
}
else 
  exit ;

echo "<h2>Logged in as ".$_SESSION['valid_user']." at line: ".__LINE__ ."</h2>";

That executes fine when I use a valid user and password and echos out the intended message:

Logged in as Conjurer at line: 56

But then when I try to use mysqli to query $conn it fails. Isn't $conn what is returned from my login function? Here is the login function - the first part uses a db_connect function to connect and returns the $conn. Then I am trying to make sure they are logged in as a valid user. If they are then I want to go on to query out some info for them.

function login($username, $passwd)
// check username and password with db
// if yes, return true
// else throw exception
{
  // connect to db
  $conn = db_connect();
  if (!$conn) echo "<h2>Connection Error for user $username using $passwd at line: ".__LINE__ ."</h2>";

  // check if username is unique
  $userquery ="select * from users where username='".$username ."'
                         and password ='".$passwd ."'";
  echo "<p>User query: ".$userquery ."</p>";
  $result = $conn->query($userquery);  


  if (!$result){	
	$errmsg = "<h2>Login query failed at line: " .__Line__."</h2>
            mysqli_connect_error: ".mysqli_connect_error()."<br />";							 
     throw new Exception($errmsg);
  }

  echo "<p> Login query ran: checking number of row results...<br />";
  if ($result->num_rows>0)
      {echo "Number of rows greater than 0 - returning true<br />";
        return true;
      }
  else 
    {$errmsg = "Number of rows NOT greater than 0 - function failed at line: " .__Line__."<br />";
     throw new Exception($errmsg);  

     }
}

Maybe I am just screwed up here, do I return a database "handle" or should I just use my connect function again because I have passed the validation part and set them as a valid user?

This part is truly confusing to me!

NogDog

$conn is local to your login() function, so is unknown outside of that script unless you either declare it as being global or assign it to a variable via a return statement in the function. As depending on a function whose purpose is to process user login to give you a value needed for database operations is sort of a non-intuitive mixture of functionalities, my recommendation would be to separate the two: start the script with code to establish your DB connection, then if necessary pass that connection variable to your login function when you call it:

// start of main script

// connect to db:
$conn = db_connect() or die("Database connection error");

// do login stuff:
if ($username && $passwd)
{
  // they have just tried logging in
  login($username, $passwd, $conn); // <-- added 3rd param for db connx
  // if they are in the database register the user id
    $_SESSION['valid_user'] = $username;
}

// rest of script...

Then your login function would not call db_connect(), and instead would just include the new parameter:

function login($username, $passwd, $conn) {

conjurer

Thanks! That cleaned it up nicely!