is a right way manage transactions using static transactionCounter with multiple classes? - php

Question

I'm interested in use the Database class described in http://php.net/manual/en/pdo.begintransaction.php
But that class has a problem, it uses a $transactionCount attribute that is not static, that means that if I have multiple classes beginning transactions it will cause multiple commits and will make my code finally go wrong, look this example (not runnable, simply for understand):
class Field extends Database {
public function createFieldToForm( $fieldName, $formId )
{
// static transactionCount = 0
// transactionCount = 0
$this->beginTransaction();
// .... createFieldToForm code ....
$last_id_new_fieldName = $this->insert( $fieldName );
$formFields = new FormFields();
$formFields->assignFieldToForm( $last_id_new_fieldName, $formId );
$this->commit();
}
public function insert( $fieldName )
{
try {
// static transactionCount = 1
// transactionCount = 1
$this->beginTransaction();
$dbh = Database::getDatabaseConnection();
$dbh->prepare( "INSERT INTO form(fieldname) VALUES (:fieldname)" );
// ... bind ...
$dbh->execute();
$this->commit();
return $dbh->lastInsertId();
}
catch (PDOException $e) {
$this->rollback();
}
}
}
class FormFields extends Database {
public function assignFieldToForm( $idFieldName, $formId )
{
// static transactionCount = 1
// transactionCount = 0
$this->beginTransaction();
// ... assign the created field to the form ....
$this->insert( $idFieldName, $formId );
$this->commit();
}
public function insert( $idFieldName, $formId )
{
try {
// static transactionCount = 2
// transactionCount = 1
$this->beginTransaction();
$dbh = Database::getDatabaseConnection();
$dbh->prepare( "INSERT INTO form_fields(idfield,formid) VALUES (:idfield,:formid)" );
// ... bind ...
$dbh->execute();
$this->commit();
}
catch (PDOException $e) {
$this->rollback();
}
}
}
const FORM_USER_INFORMATION = 3;
$fieldPhone = new Field();
$fieldPhone->createFieldToForm( "phone_number", FORM_USER_INFORMATION );
As you can see in the comments of this code the values of the $transactionCount is very different if it's static or not, but the main point of this question is about the static attribute, if is possible that its value could be changed by another code threads/functions or outside callings during the execution of (for example) createFieldToForm. What you can recommend to me to go ahead?

Answer 1

This class is not from the PHP manual but from the comments to the manual page. Which makes it deliberately unreliable source.
To solve your problem just get rid of all these "transactions". As it makes no sense to use a transaction for just a single query.
Therefore, most likely you don't need neither transactions, not counters, nor this class at all.