Question

I am trying PDO transactions for the first time. The below code doesnt work. the email address we are trying to insert has a duplicate so it should fail. It does give me an error. but the first insert get inserted into the DB and it doesnt roll back. I know rollback work cuase if i move PDO::rollBack into the Try{ before commit, it does roll back. I think the problem is its not catching the error, therefore not calling PDO::rollBack. Any ideas?

try {
    PDO::beginTransaction();

$sql = "INSERT INTO .`tblUsersIDvsAgencyID` (`id`, `agency_id`) VALUES (NULL, :agencyID)";
$STH = $this->prepare($sql); 
$STH->bindParam(':agencyID', $AgencyUser['agency_id']);
$STH->execute();
$userID = parent::lastInsertId();

$sql = "INSERT INTO `tblUsersEmailAddress` (`id`, `user_id`, `email_address`, `primary`, `created_ts`, `email_verified`) VALUES (NULL ,  :userID ,  :EmailAddress ,  '1', CURRENT_TIMESTAMP ,  '0' )";
$STH = $this->prepare($sql); 
$STH->bindParam(':userID', $userID);
$STH->bindParam(':EmailAddress', $email_address);
$STH->execute();
PDO::commit();
echo 'Data entered successfully<br />';
}
catch(PDOException $e)
{
/*** roll back the transaction if we fail ***/
PDO::rollBack();
echo "failed";
} 

Answer 1

PDO::beginTransaction() is not a static method. From your question, it looks like you’re extending the PDO class. I wouldn’t do that as I doubt you’re adding anything significant to the base class. Instead, you should the set the PDO connection as a class property.

For example

class ParentClass
{
    /**
     * @var PDO
     */
    protected $dbh;

    public function __construct(PDO $dbh)
    {
        $this->dbh = $dbh;

        // Make sure PDO is set to throw exceptions
        $this->dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    }
}

class ChildClass extends ParentClass
{
    public function insertStuff()
    {
        $this->dbh->beginTransaction();
        try {
            // do stuff

            $this->dbh->commit();
        } catch (PDOException $e) {
            $this->dbh->rollBack();
            throw $e;
        }
    }
}