Set group_concat_max_len and Select through PHP PDO

Hi experts,

I have the following PHP code
    static public function get_locations_for_reserv_details(){
         $query = 'SET SESSION group_concat_max_len=3423543543; '
                . 'SELECT, name, default_time, default_vehicle, '
                     . 'GROUP_CONCAT(DISTINCT assoc.agent_id '
                            . 'ORDER BY agents.fName, agents.lName) AS agent_ids '
                . 'FROM locations AS locs '
                    . 'INNER JOIN location_agent_assoc AS assoc '
                        . 'ON = assoc.location_id '
                    . 'INNER JOIN agents '
                        . 'ON assoc.agent_id = '    
                . 'WHERE locs.archived = 0 AND agents.archived = 0 '
                . 'GROUP BY, name, default_time, default_vehicle '
                . 'ORDER BY';
        $db = Database::getDB();
        echo '<br>' . $query . '<br>';
        $statement = $db->prepare($query);
        $result = $statement->fetchAll();
        return $result;

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However I keep getting
Fatal error: Uncaught exception 'PDOException' with message 'SQLSTATE[HY000]: General error' in C:\inetpub\wwwroot\CSS_Reservations\addedit\locations\locations.php:112 Stack trace: #0 C:\inetpub\wwwroot\CSS_Reservations\addedit\locations\locations.php(112): PDOStatement->fetchAll() #1 C:\inetpub\wwwroot\CSS_Reservations\reservations\reservations.php(834): Locations::get_locations_for_reserv_details() #2 C:\inetpub\wwwroot\CSS_Reservations\reservations\reservations.php(667): Reservations::get_booking_dependancies(Array, Array, Array, NULL, NULL, NULL, NULL, NULL, 'CSST') #3 C:\inetpub\wwwroot\CSS_Reservations\reservations\index.php(47): Reservations::display_booking_details(Array, 'existing') #4 {main} thrown in C:\inetpub\wwwroot\CSS_Reservations\addedit\locations\locations.php on line 112

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But my $query string contains the following
SET SESSION group_concat_max_len=3423543543; SELECT, name, default_time, default_vehicle, GROUP_CONCAT(DISTINCT assoc.agent_id ORDER BY agents.fName, agents.lName) AS agent_ids FROM locations AS locs INNER JOIN location_agent_assoc AS assoc ON = assoc.location_id INNER JOIN agents ON assoc.agent_id = WHERE locs.archived = 0 AND agents.archived = 0 GROUP BY, name, default_time, default_vehicle ORDER BY

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and when I run this under phpMyAdmin under the same user, it orks.  So why doesn't this work in PHP?
APD TorontoSoftware DeveloperAsked:
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Ray PaseurCommented:
Suggest you use try / catch and visualization of the exception to see what is going wrong.  The try / catch examples are given in this article.
You are probably connecting to the server using a syntax similar to:
$dbh = new PDO($dsn, $user, $password);

Instead of three parameters, try using the fourth parameter and execute the SET command:
$dbh = new PDO($dsn, $user, $password, Array(PDO::MYSQL_ATTR_INIT_COMMAND =>'SET SESSION group_concat_max_len=3423543543') );

You will of course need to modify $query so that it includes only the SELECT statement.

FYI: The options you can pass as the fourth parameter are specific to the db driver you are using.  Since you are using mysql, you'll need to look at:

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