mysql数据怎么导出

mysqldump -u [username] -p[password] [database_name] > [output_file.sql]

mysqldump -u root -p mydatabase > mydatabase_backup.sql

<?php
$host = 'localhost';
$dbname = 'mydatabase';
$user = 'root';
$pass = 'your_password';

try {
    $pdo = new PDO("mysql:host=$host;dbname=$dbname", $user, $pass);
    $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

    $sql = "SELECT * FROM your_table";
    $stmt = $pdo->query($sql);

    $output = "";
    while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
        $output .= "INSERT INTO your_table VALUES (";
        $output .= implode(", ", array_values($row));
        $output .= ");\n";
    }

    file_put_contents('exported_data.sql', $output);
    echo "Data exported successfully!";
} catch (PDOException $e) {
    echo "Error: " . $e->getMessage();
}
?>

Access denied for user 'username'@'localhost' (using password: YES)

Could not open file 'output_file.sql' for writing

SQLSTATE[HY000] [2002] No such file or directory