This  course of series give you the ability for creating your own model resource and collection , ok let's imagine you want create a simple module for persist some data like brand infos for example .

you can download file of this course and code from github

1 – Create :

First we need create our table inside our database for that you need create the Setup folder ,The path complete of module is Ibnab/Brand , inside Setup folder create  file InstallSchema.php and fill with :

 
<?php
namespace Ibnab\Brand\Setup;
use Magento\Framework\Setup\InstallSchemaInterface;
use Magento\Framework\Setup\ModuleContextInterface;
use Magento\Framework\Setup\SchemaSetupInterface;
/**
 * @codeCoverageIgnore
 */
class InstallSchema implements InstallSchemaInterface {
    /**
     * {@inheritdoc}
     */
    public function install(SchemaSetupInterface $setup, ModuleContextInterface $context) {
        $installer = $setup;
        $installer->startSetup();
        $installer->getConnection()->dropTable($installer->getTable('ibnab_brand'));
        $table = $installer->getConnection()->newTable(
            $installer->getTable('ibnab_brand')
        )->addColumn(
            'brand_id',
            \Magento\Framework\DB\Ddl\Table::TYPE_INTEGER,
            10,
            ['identity' => true, 'unsigned' => true, 'nullable' => false, 'primary' => true],
            'Slider ID'
        )->addColumn(
            'name',
            \Magento\Framework\DB\Ddl\Table::TYPE_TEXT,
            255,
            ['nullable' => false, 'default' => ''],
            'Brand title'
        )->addColumn(
            'image',
            \Magento\Framework\DB\Ddl\Table::TYPE_TEXT,
            255,
            ['nullable' => true],
            'Brand image'
        );
        $installer->getConnection()->createTable($table);
        $installer->endSetup();
    }
}
 

Magento 2 use this class inside Setup for create all needed  schema when you try to complete the  installation of your module in first time with command in terminal: php bin/magento setup:upgrade
here we use resource for unit Setup inside framework magento2 it's give core_resource for write and read from db .
Here we used 2 cool function dropTable and newTable . The injected $setup object give you an adapter for using dropTable and newTable functions ( dropTable and newTable exist inside Magento\Framework\DB\Adapter\Pdo\Mysql).

Second we need create model The path complete of module is Ibnab/Brand , create the folder model and inside it create your model Brand.php ,  with content :

 
<?php
namespace Ibnab\Brand\Model;
class Brand extends \Magento\Framework\Model\AbstractModel
{
  protected function _construct()
    {
        $this->_init('Ibnab\Brand\Model\ResourceModel\Brand');
    }
}
 

simple use case for more explain you need go to course Model Resource DB and Collection (part1) of this series

inside  Ibnab/Brand/Model/ResourceModel create Brand.php  (push):

 
<?php
namespace Ibnab\Brand\Model\ResourceModel;
class Brand extends \Magento\Framework\Model\ResourceModel\Db\AbstractDb
{
    protected function _construct()
    {
        $this->_init('ibnab_brand', 'brand_id');
    }
}
 

simple use case for more explain you need go to course Model Resource DB and Collection (part1) of this series

and inside  Ibnab/Brand/Model/ResourceModel/Brand create Collection.php (push):

 
<?php
namespace Ibnab\Brand\Model\ResourceModel\Brand;
class Collection extends \Magento\Framework\Model\ResourceModel\Db\Collection\AbstractCollection
{
    protected function _construct()
    {
        $this->_init('Ibnab\Brand\Model\Brand', 'Ibnab\Brand\Model\ResourceModel\Brand');
    }
}
 

simple use case for more explain you need go to course Model Resource DB and Collection (part2) of this series

2 – Use :

Ok let's imagine you are create simple controller inside Ibnab/Brand/Controller/Index/Index.php
 (this controller is frontend type , for testing  you need create the inside Ibnab/Brand/etc/frontend/routes.xml see inside the attachment file with this coure  ) and the content is :

 
<?php
namespace Ibnab\Brand\Controller\Index;
class Index extends \Magento\Framework\App\Action\Action
{
    protected $_brandFactory;
    public function __construct(
        \Magento\Framework\App\Action\Context $context,
        \Ibnab\Brand\Model\BrandFactory $brandFactory
    ) {
        $this->_brandFactory = $brandFactory;
        parent::__construct($context);        
    }
    public function execute()
    {
        /***create and save**/
        $brandModel = $this->_brandFactory->create();
        $brandModel->setName('Ibnab');
        //or $brandModel->setData('name','Ibnab');
        $brandModel->setImage('logo.png');
        //or $brandModel->setData('image','logo.png');
        $brandModel->save();
        var_dump($brandModel->getData());
        echo "";
        $collection = $brandModel->getCollection();
        echo "total brand is : ".$collection->count()."";
        foreach($collection as $brand):
            echo $brand->getName()."<br/ >";
            echo $brand->getImage()."<br/ >";
        endforeach;
        die();
   }
}
 

 

use can inject your model in __construct of controller (action) , but not directly we use here technique of factory for building our object (we need obtain all dependency in life cycle of object),
ok inside main function (public function execute())  , we use function create of factory for getting model brand instance of  Ibnab\Brand\Model\Brand , we can use directly setters with name of field of using the setData method (with setName we ufing the technique of magic method that take more time for compilation) , and you can use getters or directly with popular function getData.

You can get instance of class  Ibnab\Brand\Model\ResourceModel\Brand\Collection with method $brandModel→getCollection(); (you can inject directly in __construct like model Ibnab\Brand\Model\ResourceModel\Brand\CollectionFactory and get the instance with function create ) , here we use method count and we using iterator for browse all brand every loop give you an instance type   Ibnab\Brand\Model\Brand , with values of current row .