need "create a helper" to codeigniter 4 in the 2021

Do not do that. You are violating the integrity of the MVC pattern.

Better to make a model. Even simplified it is better than how you do.

Model example

PHP Code:

<?php


namespace App\Models;


use CodeIgniter\Database\ConnectionInterface;
use Config\Database;

class CommonQueries
{

    /**
     * @var ConnectionInterface
     */
    protected $db;

    public function __construct(?ConnectionInterface $db = null)
    {
        $this->db = $db ?? Database::connect();
    }

    public function getInfoSet($id = '') : ?string
    {
        $row = $this->db->table('get_info_set')
            ->select('description')
            ->where(['id' => $id])
            ->get()
            ->getFirstRow();

        return $row ? $row->description : null;
    }
} 


And helper if you needed. 

PHP Code:

if (! function_exists('get_info_set')) {
    function get_info_set($type = '') : ?string {
        return (new \App\Models\CommonQueries())->getInfoSet($type);
    }
} 


Is good code iRedds, thanks.

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