如何用php建立数据库

$servername = "localhost";

$username = "root";

$password = "password";

$conn = new PDO("Mysql:host=$servername;dbname=db_name", $username, $password);

$sql = "CREATE dataBASE db_name";

$conn->query($sql);

$sql = "CREATE Table table_name (

id INT(6) UNSIGNED AUTO_INCREMENT PRIMARY KEY,

name VARCHAR(30) NOT NULL,

age INT(3) UNSIGNED NOT NULL

)";

$conn->query($sql);

$sql = "INSERT INTO table_name (name, age) VALUES (?, ?)";

$stmt = $conn->prepare($sql);

$stmt->bind_param("ss", $name, $age);

$name = "John Doe";

$age = 30;

$stmt->execute();

$sql = "SELECT * FROM table_name";

$stmt = $conn->query($sql);

while ($row = $stmt->fetch_assoc()) {

    echo $row['name'] . '<br>';

}

$sql = "UPDATE table_name SET name = ? Where id = ?";

$stmt = $conn->prepare($sql);

$stmt->bind_param("si", $name, $id);

$name = "John Smith";

$id = 1;

$stmt->execute();

$sql = "DELETE FROM table_name WHERE id = ?";

$stmt = $conn->prepare($sql);

$stmt->bind_param("i", $id);

$id = 1;

$stmt->execute();

$conn->close();