Important note: This will only detect whether a transaction has been started using beginTransaction(). It will not be able to detect transactions started by any other means, for example by executing "START TRANSACTION".
(PHP 5 >= 5.3.3, Bundled pdo_pgsql, PHP 7, PHP 8)
PDO::inTransaction — Vérifie si nous sommes dans une transaction
Vérifie si une transaction est actuellement active dans le driver. Cette méthode ne fonctionne que pour les drivers de base de données qui supportent les transactions.
Cette fonction ne contient aucun paramètre.
Retourne true si une transaction est actuellement active, false sinon.
Important note: This will only detect whether a transaction has been started using beginTransaction(). It will not be able to detect transactions started by any other means, for example by executing "START TRANSACTION".
At least for MySQL/MariaDB, inTransaction shows the real state of the transaction since 8.0
In addition to what jlh says,
even with SQLite3 which automatically starts transaction,
inTransaction() only works after beginTransaction().
<?php
try{
$pdo = new PDO('sqlite:test.sql3', null, null, [PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION]);
var_dump($pdo->inTransaction());echo "<br>"; // bool(false) : before beginTransaction()
$pdo->beginTransaction();
var_dump($pdo->inTransaction());echo "<br>"; // bool(true) : after beginTransaction()
$pdo->rollBack();
var_dump($pdo->inTransaction());echo "<br>"; // bool(false) : after commit() or rollBack()
}catch (PDOException $e){
echo 'PDOException: ' . $e->getMessage();
}catch (Exception | ErrorException $e){
var_dump($e);
}