application/city/classes/database/frontend/city_entities/districts/class_CityDistrictsDatabaseFrontend.php

   1 <?php
   2 // Own namespace
   3 namespace Org\Mxchange\City\Database\Frontend\Districts;
   4
   5 // Import framework stuff
   6 use Org\Mxchange\CoreFramework\Database\Frontend\BaseDatabaseFrontend;
   7 use Org\Mxchange\CoreFramework\Factory\Object\ObjectFactory;
   8 use Org\Mxchange\CoreFramework\Registry\Registerable;
   9
  10 /**
  11  * A database frontend for city districts
  12  *
  13  * @author              Roland Haeder <webmaster@shipsimu.org>
  14  * @version             0.0.0
  15  * @copyright   Copyright (c) 2015, 2016 City Developer Team
  16  * @license             GNU GPL 3.0 or any newer version
  17  * @link                http://www.shipsimu.org
  18  *
  19  * This program is free software: you can redistribute it and/or modify
  20  * it under the terms of the GNU General Public License as published by
  21  * the Free Software Foundation, either version 3 of the License, or
  22  * (at your option) any later version.
  23  *
  24  * This program is distributed in the hope that it will be useful,
  25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27  * GNU General Public License for more details.
  28  *
  29  * You should have received a copy of the GNU General Public License
  30  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  31  */
  32 class CityDistrictsDatabaseFrontend extends BaseDatabaseFrontend implements CityDistrictsFrontend, Registerable {
  33         // Constants for database table names
  34         const DB_TABLE_CITY_DISTRICTS = 'city_districts';
  35
  36         // Section id, an referenced city id and district id
  37         const DB_COLUMN_CITY_ID                = 'city_id';
  38         const DB_COLUMN_DISTRICT_ID            = 'district_id';
  39
  40         /**
  41          * Protected constructor
  42          *
  43          * @return      void
  44          */
  45         protected function __construct () {
  46                 // Call parent constructor
  47                 parent::__construct(__CLASS__);
  48         }
  49
  50         /**
  51          * Creates an instance of this database frontend by a provided user class
  52          *
  53          * @return      $frontendInstance       An instance of the created frontend class
  54          */
  55         public static final function createCityDistrictsDatabaseFrontend () {
  56                 // Get a new instance
  57                 $frontendInstance = new CityDistrictsDatabaseFrontend();
  58
  59                 // Set (primary!) table name
  60                 $frontendInstance->setTableName(self::DB_TABLE_CITY_DISTRICTS);
  61
  62                 // Return the instance
  63                 return $frontendInstance;
  64         }
  65
  66         /**
  67          * Checks if the given city id is found in districts table
  68          *
  69          * @param       $cityId         City id to check
  70          * @return      $isFound        Whether the city id is found
  71          */
  72         public function ifCityHasDistricts (int $cityId) {
  73                 // Get search instance
  74                 $searchInstance = ObjectFactory::createObjectByConfiguredName('search_criteria_class');
  75
  76                 // Search for 'city_id'
  77                 $searchInstance->addCriteria(self::DB_COLUMN_CITY_ID, $cityId);
  78
  79                 /*
  80                  * Only one entry is enough to find, else this query could run very
  81                  * long on large maps.
  82                  */
  83                 $searchInstance->setLimit(1);
  84
  85                 // Execute it on database instance
  86                 $resultInstance = $this->doSelectByCriteria($searchInstance);
  87
  88                 // Check if there is one entry
  89                 $isFound = $resultInstance->next();
  90
  91                 // Return result
  92                 return $isFound;
  93         }
  94 }