crm-summit/app/Models/ZonesModel.php

<?php namespace App\Models;

use CodeIgniter\Model;

class ZonesModel extends Model {

	protected $table 		= 'zones';
	protected $primaryKey 	= 'zoneid';
	protected $allowedFields = [ 'zonecode', 'zoneclass', 'parentzoneid', 'zonename' ];

	public function getAllProvinces() {
		$this->select('zoneid, zonename')->where('parentzoneid IS NULL', null, false);

		// if (!empty($filters['zoneid'])) {
		// 	$this->where('zoneid', $filters['zoneid']);
		// }
		// if (!empty($filters['zonename'])) {
		// 	$this->like('zonename', $filters['zonename'], 'both');
		// }

		return $this->findAll();
	}

	public function getAllCities($filter = []) {
		$rows = $this->select('zoneid, zonename')->where('parentzoneid IS NOT NULL', null, false);

		if (!empty($filter['zoneid'])) {
			$this->where('parentzoneid', $filter['zoneid']);
		}

		return $this->findAll();
	}

}