Magento2

go to this file

/Magento/Framework/View/Element/Template/File/Validator.php

replace this part

foreach ($directories as $directory) {
    if (0 === strpos($realPath, $directory)) {

with the following one:

$isWin = 'WIN' === strtoupper(substr(PHP_OS, 0, 3)); 

/** @var bool $isWin */ 
foreach ($directories as $directory) { 
    if (0 === strpos($realPath, !$isWin ? $directory : $this->fileDriver->getRealPath($directory)) ) {

Original article 

How to Add Admin User via Command Line

php bin/magento admin:user:create --admin-user=wikicode  --admin-password=WiKiLoveMagento [email protected] --admin-firstname=Wiki  --admin-lastname=Code

the best way to do do this is using the below method

$objectManager =   \Magento\Framework\App\ObjectManager::getInstance();
$productR =      $objectManager ->create('\Magento\Catalog\Api\ProductRepositoryInterface');
$product = $productR->get('product_sku');
$product->cleanCache();
$this->_eventManager->dispatch('clean_cache_by_tags', ['object' => $product]);

you need of course to follow the DI to implement this code, I just used this quick way to make it easy to understand

Using Object Manager

$storeManager = $objectManager->get('\Magento\Store\Model\StoreManagerInterface');
$websiteId = $storeManager->getStore()->getWebsiteId();
 
$objectManager = \Magento\Framework\App\ObjectManager::getInstance();
$customerRepository = $objectManager->create('Magento\Customer\Api\CustomerRepositoryInterface');
 
// load customer info by email
$customer = $customerRepository->get('[email protected]', $websiteId);
 
// load customer info by id    
$customer = $customerRepository->getById(1);
 
// Update customer Info
$cust

use this query to see  all products that do not have images in magento2

SELECT sku FROM `catalog_product_entity` WHERE `entity_id` not in (SELECT `entity_id` FROM `catalog_product_entity_media_gallery_value` )

ignoring the "Not Visible Individually" products

you have to add this code to the block or to the page

 {{block class="Magento\Framework\View\Element\Template"  template="{Vendor}_{Module}::pages/example.phtml"}}

Example 

{{block class="Magento\Catalog\Block\Product\ListProduct" category_id="50" name="home.products.list.custom" template="Magento_Catalog::product/list.phtml"}} 

{{widget type="Magento\Catalog\Block\Category\Widget\Link" anchor_text="MY Custom category" title="Custom Category" template="category/widget/link/link_block.phtml" id_path="category/12"}}

there are three templates

Magento profiler can help you with the store performance tuning before the store release or during the exploitation.
The old UI for enabling/disabling the profiler is not available in Magento 2 and the profiler is disabled by default.
To enable one of the profiler formats mentioned above, you can edit .htaccess (a configuration file for Apache Web Server software):

    Choose one of the next expressions:

Most of us wanted or liked to change the Maintenance Page content, but it had difficulties doing that, now we will show you how easy is that can be

From the Magento root directory, switch to production mode:

 bin/magento deploy:mode:set production

Enable JavaScript bundling:

 bin/magento config:set dev/js/enable_js_bundling 1

Optimize bundling by minifying JavaScript files:

 bin/magento config:set dev/js/minify_files 1

Enable cache busting on static file URLs. This ensures users get the latest version of the assets anytime they update: