There are restrictions on the placeholder string. In the following code the first execute fails with a SQLSTATE[HY093]. It is not clear exactly what characters are allowed.
<?php declare(strict_types=1);
$db = new \PDO("mysql:hostname=localhost;dbname=minidwh", "minidwh", "Meisterstueck!");
$db->query("SET NAMES 'utf8mb4'");
$db->query("DROP TABLE IF EXISTS `äëïöüß`");
$db->query("CREATE TABLE `äëïöüß` ( `id` INT NOT NULL AUTO_INCREMENT, PRIMARY KEY (`id`) ) ENGINE = ARIA;");
$db->query("ALTER TABLE `äëïöüß` ADD COLUMN `äëïöüß` TEXT NULL");
try {
$stmt = $db->prepare("INSERT INTO `äëïöüß` (`äëïöüß`) VALUES (:äëïöüß)");
$result = $stmt->execute([':äëïöüß' => 'test1']);
} catch (\PDOException $e) {
echo $e->getMessage() . '<BR>';
}
try {
$stmt = $db->prepare("INSERT INTO `äëïöüß` (`äëïöüß`) VALUES (?)");
$result = $stmt->execute(['test2']);
} catch (\PDOException $e) {
echo $e->getMessage() . '<BR>';
}
try {
$stmt = $db->prepare("INSERT INTO `äëïöüß` (`äëïöüß`) VALUES (:column)");
$result = $stmt->execute([':column' => 'test3']);
} catch (\PDOException $e) {
echo $e->getMessage() . '<BR>';
}
try {
$stmt = $db->prepare("INSERT INTO `äëïöüß` (`äëïöüß`) VALUES (:column)");
$stmt->bindValue(':column', 'test4');
$result = $stmt->execute();
} catch (\PDOException $e) {
echo $e->getMessage() . '<BR>';
}
