backend_update.php

<?php

namespace App;

/**
 * PHP SQLite Update Demo
 */
class SQLiteUpdate {

    /**
     * PDO object
     * @var \PDO
     */
    private $pdo;

    /**
     * Initialize the object with a specified PDO object
     */
    public function __construct($pdo) {
        $this->pdo = $pdo;
    }

    /**
     * Mark a task specified by the task_id completed
     * @param type $taskId
     * @param type $completedDate
     * @return bool true if success and falase on failure
     */
    public function completeTask($taskId, $completedDate) {
        // SQL statement to update status of a task to completed
        $sql = "UPDATE tasks "
                . "SET completed = 1, "
                . "completed_date = :completed_date "
                . "WHERE task_id = :task_id";

        $stmt = $this->pdo->prepare($sql);

        // passing values to the parameters
        $stmt->bindValue(':task_id', $taskId);
        $stmt->bindValue(':completed_date', $completedDate);

        // execute the update statement
        return $stmt->execute();
    }
}