Issues using PHP MySQL Built-In Functions inside a class - php

Question

I am working with a MySQL Database and having some issues while trying to get data from several built-in PHP MySQL methods. I have written a class to interact with the database, and here are the relevant bits:
<?php
include("includes/Config.inc.php");
include_once("ChromePHP.class.php");
class Database{
private $db;
private $hostname;
private $username;
private $password;
private $schema;
function __construct() {
if(func_num_args() == 0){
$this->hostname = conf_hostname;
$this->username = conf_username;
$this->password = conf_password;
$this->schema = conf_schema;
}
else{
$params = func_get_args();
$this->hostname = $params[0];
$this->username = $params[1];
$this->password = $params[2];
$this->schema = $params[3];
}
$this->open();
}
private function open(){
$this->db = mysql_connect($this->hostname, $this->username, $this->password) or die ('Error connecting to mysql');
mysql_select_db($this->schema, $this->db);
mysql_query("SET NAMES utf8");
}
public function executeQuery($query){
$results = mysql_query($query, $this->db) or die ("Error in query: $query. ".mysql_error());
return $results;
}
public function executeNonQuery($query){
mysql_query($query, $this->db) or die ("Error in query: $query. ".mysql_error());
$info = mysql_info($this->db);
if($info){
$bits = explode(' ', $info);
return $bits[4];
}
return false;
}
public function close(){
mysql_close($this->db);
}
public function escape($string){
$output = mysql_real_escape_string($string , $this->db);
return $output;
}
public function getRegionTree(){
$query = "SELECT COUNT(parent.Name) - 2 as level, node.Name AS Name, node.ID, node.Parent
FROM Region AS node, Region AS parent
WHERE node.LeftVal BETWEEN parent.LeftVal AND parent.RightVal and node.Name <> 'Earth'
GROUP BY node.ID
ORDER BY node.LeftVal";
$result = $this->executeQuery($query);
$last_level = 0;
$output = '<ul id="regionTree">'.PHP_EOL;
while ($row = mysql_fetch_assoc($result)) {
$link = '<li>'.PHP_EOL.''.$row["Name"]."".PHP_EOL;
$diff = $last_level - $row["level"];
if($diff == 0){
// Sibling
$output .= ($row["level"] != 0) ? '</li>'.PHP_EOL.$link:$link;
}
elseif($diff < 0){
// Child
$demoter = '<ul>'.PHP_EOL;
for ($i=0; $i > $diff; $i--) {
$output .= $demoter;
}
$output .= $link;
}
else{
// Parent
$promoter = '</li>'.PHP_EOL.'</ul>';
for ($i=0; $i < $diff; $i++) {
$output .= ($row["level"] != 0) ? $promoter.PHP_EOL."</li>":$promoter;
}
$output .= $link;
}
$last_level = $row["level"];
}
$output .= "</li></ul>";
return $output;
}
public function addRegion($name, $type, $parentID){
$query = "select Name, Region_Type from Region where ID = ".$parentID;
$result = $this->executeQuery($query);
if($result){
$row = mysql_fetch_assoc($result);
$query = "call AddRegion('".$name."', '".$type."', '".$row["Name"]."', '".$row["Region_Type"]."', #returnCode, #returnMessage)";
$result = $this->executeQuery($query);
if($result){
return true;
}
else{
$query = "select #returnCode as code, #returnMessage as message";
$result = $this->executeQuery($query);
while($row = mysql_fetch_assoc($result)){
print_r($row);
}
return false;
}
}
return false;
}
public function getInfo(){
return mysql_info();
}
public function editRegion($id, $name, $type){
$query = "update Region set Name = '$name', Region_Type = '$type' where ID = $id";
if($this->executeNonQuery($query) > 0){
return true;
}
return false;
}
}
$db = new Database();
?>
With this Database class I am able to successfully make queries, get region trees, and successfully change data in the database using the ExecuteNonQuery function. However, any attempts I have made to use mysql_info, mysql_affected_rows, or other similar functions fails, making it really difficult to write any error handling code. To make matters stranger yet, if I run the following code:
<?php
$db = mysql_connect("localhost", "User", "Password") or die ('Error connecting to mysql');
mysql_select_db("DB", $db);
mysql_query("update Region set Name = 'test' where ID = 594", $db);
echo mysql_info($db);
?>
I am able to get results as expected. Any Ideas?

Answer 1

Are you using mysql_info and mysql_error outside the Database class? And if so how are you referencing the database connection? If you don't identify the database connection then:
The MySQL connection. If the link identifier is not specified, the last
link opened by mysql_connect() is assumed. If no such link is found,
it will try to create one as if mysql_connect() was called with no
arguments. If no connection is found or established, an E_WARNING
level error is generated.
So internally you should be doing mysql_info($this->db); to get mysql_info. Accessing $db externally requires you to write something to get around it being private.
But if you are going to be doing database stuff in an object-oriented mode you really should investigate PDO.

Answer 2

After adding "or die()" statements in several places in my script, I was surprised to see that nothing was actually failing to work, instead it was failing to work the way I expected it to. The problem I was having as it turns out, was that splitting the output of mysql_info (on the space character) resulted in several indices in the array containing nothing, as would be generated by inconsistent whitespace in the output of mysql_info. The index that I thought (based upon counting spaces visually) would contain an integer instead contained a string, and I was attempting to compare that string against the number 0, which won't work. I have updated my executeNonQuery function as follows:
public function executeNonQuery($query){
mysql_query($query, $this->db) or die ("Error in query: $query. ".mysql_error());
$info = mysql_info($this->db);
if($info){
$output = array();
$bits = explode(' ', $info);
$output["rowsMatched"] = $bits[2];
$output["rowsChanged"] = $bits[5];
$output["warnings"] = $bits[8];
return $output;
}
return false;
}