其中会话数据为Sql

I would like to have an sql query, in which the session data 'id' equals a variable. Currently I have this query to fetch events from calendar :

<?php
// List of events
 $json = array();

 // Query that retrieves events
 $requete = "  SELECT * FROM `evenement` LEFT JOIN `evenementontvanger` ON `evenementontvanger`.`idEvent` = `evenement`.`id` WHERE `idEvent`=`evenement`.`id`";

 // connection to the database
 try {
 $bdd = new PDO('mysql:host=localhost;dbname=blackboks-calendar', 'root', 'root');
 } catch(Exception $e) {
  exit('Unable to connect to database.');
 }
 // Execute the query
 $resultat = $bdd->query($requete) or die(print_r($bdd->errorInfo()));

 // sending the encoded result to success page
 echo json_encode($resultat->fetchAll(PDO::FETCH_ASSOC));

?>

And I think the answers should be something like this:

$requete = "  SELECT * FROM `evenement` LEFT JOIN `evenementontvanger` ON `evenementontvanger`.`idEvent` = `evenement`.`id` WHERE `idWerknemer`=`"$this->session_data['id']"`";

It should be as

$requete = " SELECT * FROM `evenement` 
    LEFT JOIN `evenementontvanger` ON `evenementontvanger`.`idEvent` = `evenement`.`id` 
    WHERE `idWerknemer`='".$this->session_data['id']."'";

The string data should be enclosed with single quote '', if its integer you need not provide ''