下面的测试程序在我尝试过的所有平台上都产生了预期的答案“1”，除了一家托管公司的平台，它给出了“0”。有人能想到为什么会这样吗？MySQL版本8.0.26和PHP 8.2.9。

<?php

error_reporting(-1);
ini_set('display_errors', '1');

$db_database = "your_database";
$db_host = 'localhost';
$db_login = "your_login";
$db_password = "your_password";

$dsn = "mysql:dbname=$db_database;host=$db_host";
$table = "found_rows_test";

$options = [PDO::MYSQL_ATTR_FOUND_ROWS => true];

$dbh = new PDO($dsn, $db_login, $db_password, $options);

$sql = "CREATE TABLE IF NOT EXISTS $table (id varchar(10), data int, PRIMARY KEY(id))";
$stmt = $dbh->prepare($sql);
$stmt->execute();

$sql = "INSERT IGNORE INTO $table (id, data) VALUES ('abcd', 1)";
$stmt = $dbh->prepare($sql);
$stmt->execute();

$sql = "UPDATE $table SET data=1 WHERE id='abcd'";
$stmt = $dbh->prepare($sql);
$stmt->execute();

echo $stmt->rowCount();

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