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)) {
            $link = '<li>'.PHP_EOL.'<a href="#" data-self="'.$row["ID"].'" data-parent="'.$row["Parent"].'">'.$row["Name"]."</a>".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

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;
}