[SOLVED] PHP Inheritance?... "supplied argument is not a valid MySQL"

[szym9341]

This is a continuation of another problem that I was having... I have two classes (dbConnector & getTodoCats) and one script.  When I use 'or die(mysql_error());' in my query function I get:

 

Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in /mydirectories/dbConnector.php on line 42  If you have any idea why this is occurring, please help... when I take off the 'mysql_error', the page works fine.

 

The script:

 

<?php
ini_set('display_errors', '1');
error_reporting(E_ALL);

require_once('../_library/getTodoCats.php');

$si = '';
$si['additional'][0] = " WHERE t1.project_id = '365'";
$data = new getTodoCats($si);
$data = $data->getAllData();
foreach ($data as $i) {
  echo $i['todo_cat'];;
}
?>

 

getTodoCats Class:

 

<?php
require_once('dbConnector.php');

class getTodoCats {
  public $sql;

  function __construct($si = "") {

    // limit select, if needed
if ((isset($si['select']) && ($si['select'] != NULL))) {
  $select = $si['select'];
} else {
  $select = '*';
}

// foundational SQL
    $this->sql = "SELECT $select
                  FROM todo_cats AS t1
			  ";
    
    // additional SQL, if needed	
    if ($si['additional'] != NULL) {
      foreach ($si['additional'] as $i) {
      $this->sql .= " $i";
      }
    }
  }

  function getSql() {
    return $this->sql;
  }

  function getNumRows() {
    $dbConnector = new dbConnector('main'); 
$query = $dbConnector->query($this->sql);
$num = $dbConnector->getNumRows($query);
    return $num;
  }	  

  function getAllData() {
    $dbConnector = new dbConnector('main');
    $sql = $dbConnector->query($this->sql); 
    $i = 0;
    $thedata = array();
    while ($row = $dbConnector->getArray($sql)) {
  $thedata[$i]['todo_cat_id'] = $row['todo_cat_id'];
  $thedata[$i]['todo_cat'] = $row['todo_cat'];
  $thedata[$i]['project_id'] = $row['project_id'];
      $i++;
    }
    return $thedata;
  }
}  
?>

 

the dbConnector class:

 

<?php
require_once ('/home/szym9341/includes/systemComponent.php');

class dbConnector extends systemComponent {

  public $theQuery;
  public $link;

  function __construct($which_db) {

    // Load settings from parent class
    $settings = systemComponent::getSettings();
    
if ($which_db == 'main') {
  // array of zero = main database; add else if for another connection
      $host = $settings[0]['dbhost'];
      $db = $settings[0]['dbname'];
      $user = $settings[0]['dbusername'];
      $pass = $settings[0]['dbpassword'];
}

    // Connect to the database
    $this->link = mysql_connect($host, $user, $pass);
    mysql_select_db($db);

  }
  
  //*** Function: query, Purpose: Execute a database query ***
  function query($query) {
    $this->theQuery = $query;
     // return mysql_query($query, $this->link);
     return mysql_query($query, $this->link) or die(mysql_error());
  }

  //*** Function: getNumRows, Purpose: Return row count, MySQL version ***
  function getNumRows($result){
    return mysql_num_rows($result);
  }

  //*** Function: fetchArray, Purpose: Get array of query results ***
  function getArray($query) {
    return mysql_fetch_array($query);
  }
}
?>

[PFMaBiSmAd]

It would appear that you are overwriting your $data object with an array of data. $data is no longer an instance of your class after this point in the code -

 

$data = $data->getAllData();

[szym9341]

Thanks for the reply.  I was desperately hoping this would fix the problem, so I changed the script to the following, but the warning still appears.

 

warning:

Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in /dirs/dbConnector.php on line 42

 

changed script:

 

$si = '';
$si['additional'][0] = " WHERE t1.project_id = '365'";
$data = new getTodoCats($si);
$hmm2 = $data->getAllData();
foreach ($hmm2 as $i) {
  echo $i['todo_cat'];;
}

[PFMaBiSmAd]

Is the posted code for the query() function current, it still has the or die(...) statement in it?

 

I don't see any obvious problems. Is there any other code that is calling the getAllData() or getArray() functions?

[szym9341]

Thanks again for the reply... I've stripped everything down to bare minimum and still getting the warning flag.  Yes, the 'or die()' is still part of the query function.  When I take away the 'or die(mysql_error()' the array prints fine... no warnings/errors...

 

Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in /dirs/tester.php on line 31

 

updated in total (tester.php):

 

<?php
ini_set('display_errors', '1');
error_reporting(E_ALL);

require_once ('/dirs/systemComponent.php');

class dbConnector extends systemComponent {

  public $link;

  function __construct() {
  
    $settings = systemComponent::getSettings();
    
    $host = $settings[0]['dbhost'];
    $db = $settings[0]['dbname'];
    $user = $settings[0]['dbusername'];
    $pass = $settings[0]['dbpassword'];

    $this->link = mysql_connect($host, $user, $pass);
    mysql_select_db($db);

  }

  function query($query) {
    return mysql_query($query, $this->link) or die(mysql_error());
  }

  function getArray($query) {
    return mysql_fetch_array($query);
  }
}

$sql = "SELECT * FROM todo_cats";
$dbConnector = new dbConnector();
$query = $dbConnector->query($sql);
$row = $dbConnector->getArray($query);
print_r($row);
?>

[PFMaBiSmAd]

I have seen a problem "returning" the output from a function call (specifically a mysql_query()) and the php manual hints that it does not work (I suspect it depends on what function is called and if it is internally written correctly). Try changing the following -

 

    return mysql_query($query, $this->link) or die(mysql_error());

 

to this -

 

    $result = mysql_query($query, $this->link) or die(mysql_error());

    return $result;

 

Edit: Actually if you want to test that before you make the modification, use var_dump() on the $query variable -

 

$query = $dbConnector->query($sql);

var_dump($query);

$row = $dbConnector->getArray($query);

 

I believe you will get a NULL out.

[szym9341]

YESSSSSSSSS!

 

Thank you! Whew, that threw me for a loop. 

 

Thanks again!

[PFMaBiSmAd]

I'm not sure if this is a bug or just poor documentation. mysql_query() can return a BOOL or a resource depending if the query works or fails and even what kind of query, so it might take assigning the results to a variable to "fix" exactly what type it is so that the return statement can properly use it.