How can PHP developers ensure data consistency in a multi-user system to prevent data loss during simultaneous updates?

To ensure data consistency in a multi-user system and prevent data loss during simultaneous updates, PHP developers can implement database transactions. By using transactions, developers can group multiple SQL queries into a single unit of work that either all succeed or all fail, maintaining data integrity. 

// Establish a database connection
$pdo = new PDO('mysql:host=localhost;dbname=database', 'username', 'password');

// Begin a transaction
$pdo->beginTransaction();

try {
    // Perform multiple SQL queries within the transaction
    $pdo->exec("UPDATE table SET column = 'new_value' WHERE id = 1");
    $pdo->exec("UPDATE table SET column = 'another_value' WHERE id = 2");

    // Commit the transaction if all queries succeed
    $pdo->commit();
} catch (PDOException $e) {
    // Rollback the transaction if an error occurs
    $pdo->rollBack();
    echo "Transaction failed: " . $e->getMessage();
}

Keywords

concurrency control transactions locking mechanisms isolation levels database triggers

Related Questions