<?php

function fetchPost($table): object
{
    $data = [];

    try {
        $this->db->query("SELECT id, title, body FROM $table ORDER BY id DESC ");
        $rows = $this->db->fetchAll();

        // Map the data and apply changes
        $data = array_map(static function ($row) {
            return $row;
        }, $rows);

        // Or directly apply rows to the data
        $data = $this->db->fetchAll();
    } catch (Exception $e) {
        return (object)[
            'error' => true,
            'message' => sprintf(
                'Check %s class on %s method: %s',
                'SelectPosts',
                __METHOD__,
                $e->getMessage()
            )
        ];
    }

    $hasData = count($data) > 0;

    return (object)[
        'error' => $hasData,
        'data' => $data,
        'message' => $hasData ?
            'OK' :
            'No Data Found'
    ];
}

// index.phtml
$posts = fetchPost('posts');

if (!$posts->error) {
    echo sprintf('<div class="error">%s</div>', $posts->message);
} else {
    array_map(static function ($item) {
        // Process item and render needed data
    }, $posts->data);
}