问如何在PHP中使用MySQLi的多个准备语句？

EN

<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");

/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}

/* set autocommit to off */
$mysqli->autocommit(FALSE);

/* Insert some values */
$mysqli->query("INSERT INTO table1 VALUES ('DEU', 'Bavarian', 'F', 11.2)");
$mysqli->query("INSERT INTO table2 VALUES ('DEU', 'Bavarian', 'F', 11.2)");

/* commit transaction */
$mysqli->commit();

/* close connection */
$mysqli->close();

<?php
$mysqli = new mysqli("localhost", "root", "", "");

/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}

/* set autocommit to off */
$mysqli->autocommit(FALSE);

$stmt1 = $mysqli->prepare("INSERT INTO tbl1 (id, intro) VALUES (?, ?)");
$stmt2 = $mysqli->prepare("INSERT INTO tbl2 (id, name) VALUES (?, ?)");

$str1 = 'abc';
$str2 = 'efg';
$str3 = 'hij';
$str4 = 'klm';

$stmt1->bind_param('ss', $str1, $str2);
$stmt2->bind_param('ss', $str3,$str4);

if ($stmt1->execute() == false)
{
    echo 'First query failed: ' . $mysqli->error;
}
$stmt1->close();
if ($stmt2->execute() == false)
{
    echo 'Second query failed: ' . $mysqli->error;
}
$stmt2->close();
$mysqli->close();