mysqli 获取错误信息

$mysqli = new mysqli("localhost", "user", "password", "database");

if ($mysqli->connect_errno) {
    echo "Failed to connect to MySQL: " . $mysqli->connect_error;
    exit();
}

$sql = "SELECT * FROM non_existent_table"; // 假设这个表不存在
$result = $mysqli->query($sql);

if (!$result) {
    echo "Query failed: " . $mysqli->error;
}

$mysqli->close();

$mysqli = new mysqli("localhost", "user", "password", "database");

if ($mysqli->connect_errno) {
    echo "Failed to connect to MySQL: " . $mysqli->connect_error;
    exit();
}

$sql = "SELECT * FROM non_existent_table";
$result = $mysqli->query($sql);

if (!$result) {
    echo "Query failed: " . $mysqli->error;
}

$mysqli->close();