How to change attribute dropdown type to multi-select in Magento 2?

Short Answer:

Not possible via Magento2 Admin Backend.

Solution:

You need to update eav_attribute table and edit information about backend_source, frontend_input etc.

Simple query for that is:

UPDATE `eav_attribute` SET `backend_model`="Magento\\Eav\\Model\\Entity\\Attribute\\Backend\\ArrayBackend", `backend_type`="varchar", `frontend_input`="multiselect", `source_model`=NULL WHERE `attribute_id`=YOUR_ATTRIBUTE_ID_INTEGER LIMIT 1

Replace YOUR_ATTRIBUTE_ID_INTEGER with your attribute_id like 355

Reference:

https://stackoverflow.com/a/57701845/2229148

How to disable products in Magento2 which dont have any gallery image?

UPDATE `catalog_product_entity_int` SET `value`=2 where `entity_id` in (SELECT a.`entity_id` FROM `catalog_product_entity` AS a LEFT JOIN `catalog_product_entity_media_gallery_value` AS b ON a.entity_id = b.entity_id LEFT JOIN `catalog_product_entity_media_gallery` AS c ON b.value_id = c.value_id WHERE c.value IS NULL) and `attribute_id` = 96

It is SQL query

Assumption:

value=2 means disable and value=1 means enable

attribute_id=96 means “status” attribute

References:

https://gist.github.com/tegansnyder/8464261#gistcomment-2910808

https://magento.stackexchange.com/a/83033/32283

How to wipe all the tables and data in MySQL? Clean whole database

SET FOREIGN_KEY_CHECKS = 0;
SET GROUP_CONCAT_MAX_LEN=32768;
SET @tables = NULL;
SELECT GROUP_CONCAT('`', table_name, '`') INTO @tables
  FROM information_schema.tables
  WHERE table_schema = (SELECT DATABASE());
SELECT IFNULL(@tables,'dummy') INTO @tables;
 
SET @tables = CONCAT('DROP TABLE IF EXISTS ', @tables);
PREPARE stmt FROM @tables;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;
SET FOREIGN_KEY_CHECKS = 1;

Will not work via phpmyadmin or any script. this has to be run in cmd/terminal

Quick Command

wget https://gist.githubusercontent.com/harshvardhanmalpani/e670a8de7aa81673364dd48f125cb9ac/raw/ce04b319bf1594d148d3346e1474119fe1cd1b3f/flushdb.sql

mysql -hYOUR_DATABASE_HOSTNAME -uYOUR_DATABASE_USER -p YOUR_DATABASE_NAME < flushdb.sql

Source:
https://gist.github.com/harshvardhanmalpani/e670a8de7aa81673364dd48f125cb9ac

How to remove sign in popup from Magento 2 checkout page?

Magento2 has this authentication pop up on checkout page, which many store owners wont like to see on their checkout page.

Background of this pop up area and Related files

The pop up itself is generated by Magento_Customer::account/authentication-popup.phtml

But this pop up works very differently on checkout page. In fact this is a separate pop up than the one you see in header area. It is embedded in a series of js files which are governed by knockout-js

Other file responsible is: vendor/magento/module-checkout/view/frontend/web/js/proceed-to-checkout.js

Here is how to remove it finally

Edit file or overload the file

app/design/frontend/YourVendor/YourTheme/Magento_Checkout/web/template/onepage.html

delete the following lines and save the file

<!-- ko foreach: getRegion('authentication') -->
<!-- ko template: getTemplate() --><!-- /ko -->
<!--/ko-->

Reference:

https://github.com/magento/magento2/blob/2.2/app/code/Magento/Checkout/view/frontend/web/template/onepage.html

https://github.com/magento/magento2/blob/fc66fe443d87c4e69fe9022d7c95fe66e0565978/app/code/Magento/Checkout/view/frontend/layout/checkout_index_index.xml#L39

How to show correct item count in Magento 2 Checkout Order summary?

By default, app/design/Magento/Checkout/view/frontend/web/template/summary/cart-items.html file is being used
Or vendor/magento/module-checkout/view/frontend/web/template/summary/cart-items.html

To overload this file, create file cart-items.html in your theme folder. Make sure you place the file in Magento_Checkout/web/template/summary/

Edit the line

<span data-bind="text: getCartLineItemsCount()"></span>

And replace it with

<span data-bind="text: getItemsQty()"></span>

Reference Files:

vendor/magento/module-checkout/view/frontend/web/js/view/summary/cart-items.js

https://github.com/magento/magento2/blob/2.2/app/code/Magento/Checkout/view/frontend/web/template/summary/cart-items.html

https://github.com/magento/magento2/blob/2.2/app/code/Magento/Checkout/view/frontend/web/js/view/summary/cart-items.js

How to dump all options for any attribute in Magento 2 programmatically?

The following code does not adhere to Magento’s developer recommendations. Using object manager in such a way externally is a TERRIBLE idea.

Comment out line number 2 and then run the script. Edit line 11 and put the attribute code you want to dump

<?php
header("Location: /");exit;
use \Magento\Framework\App\Bootstrap;
error_reporting(E_ALL);
ini_set("display_errors", 1);
include('./app/bootstrap.php');
$bootstrap     = Bootstrap::create(BP, $_SERVER);
$objectManager = $bootstrap->getObjectManager();

$eavConfig = $objectManager->get('\Magento\Eav\Model\Config');
$attribute = $eavConfig->getAttribute('catalog_product', 'manufacturer');
$options   = $attribute->getSource()->getAllOptions();
$options   = array_slice($options, 1);
usort($options, function($a, $b)
{
    return strcasecmp($a['label'], $b['label']);
});
if (count($options))
    $v = "<table>";
foreach ($options as $option) {
    $v .= "<tr><td>" . $option['value'] . '</td><td>' . $option['label'] . '</td></tr>';
}
if (count($options))
    $v .= "</table>";
echo $v;
?>
   <style>
    table tr:nth-child(odd){background:#444;color:#fff}
   </style>

How to customize Magento 2 Maintenance mode page?

Edit the file pub/errors/default/503.phtml and put the following code

<?php
/**
 * How to edit and customize code of Magento 2 Maintenance 503 Page
 * Add analytics if any
 * Replace <COMPANY NAME> with your Organization Name
 */
?>
<!doctype html>
<title>Site Maintenance</title>
<style>
  body { text-align: center; padding: 150px; }
  h1 { font-size: 50px; }
  body { font: 20px Helvetica, sans-serif; color: #333; }
  article { display: block; text-align: left; width: 650px; margin: 0 auto; }
  a { color: #dc8100; text-decoration: none; }
  a:hover { color: #333; text-decoration: none; }
</style>

<article>
    <h1>We&rsquo;ll be back soon!</h1>
    <div>
        <p>Sorry for the inconvenience but we&rsquo;re performing some maintenance at the moment. If you need to you can always <a href="mailto:[email protected] NAME">contact us</a>, otherwise we&rsquo;ll be back online shortly!</p>
        <p>&mdash; Team COMPANY NAME</p>
    </div>
</article>

How to hide a specific category from Google Index in Magento 2?

In Magento Admin Panel, Go to Catalog in Left Menu > Categories
Select the category you want to edit and in Design Section > Layout Update XML, put this value:

<head>
    <meta name="robots" content="NOINDEX,NOFOLLOW"/>
</head>
How to add noindex nofollow on specific category page in Magento2

Save the category and then Clear the cache