safekat/ci4/app/Models/Configuracion/ConfiguracionSistemaModel.php

<?php
namespace App\Models\Configuracion;

class ConfiguracionSistemaModel extends \App\Models\BaseModel
{
    protected $table = "configuracion_sistema";

    /**
     * Whether primary key uses auto increment.
     *
     * @var bool
     */
    protected $useAutoIncrement = true;

    protected $allowedFields = ["var_name", "value", "datatype"];
    protected $returnType = "App\Entities\Configuracion\ConfiguracionSistemaEntity";

    public static $labelField = "var_name";

    protected $validationRules = [
    ];

    protected $validationMessages = [
    ];

    public function getPOD()
    {
        $builder = $this->db
            ->table($this->table . " t1")
            ->select(
                '(SELECT CAST(t1.value AS INT)) AS POD', false)
            ->where('t1.var_name', 'POD');

        $POD = intval($builder->get()->getFirstRow()->POD);
        return $POD;
    }
}