Update Product Custom Attribute Scope in Magento 2

Here we learn in Magento2 – How to update the product custom attribute’s scope in the custom module.
If you want to create a new custom attribute in Magento 2, you can check the wonderful blog here

If there is an attribute with store view scope.

1st Method: Using the UpgradeData file

First, we need to create a file named UpgradeData.php in our custom module Setup folder.
complete path: app/code/ModuleNameSpace/YourModuleName/Setup/UpgradeData.php

<?php

namespace ModuleNameSpace\YourModuleName\Setup;

use Magento\Framework\Setup;
use Magento\Eav\Setup\EavSetupFactory;

class UpgradeData implements Setup\UpgradeDataInterface 
{
    /**
     * EAV setup factory
     *
     * @var EavSetupFactory
     */
    private $_eavSetupFactory;
    /**
     * @param EavSetupFactory  $eavSetupFactory
     */
    public function __construct(
        EavSetupFactory $eavSetupFactory
    ) {
        $this->_eavSetupFactory = $eavSetupFactory;
    }

    public function upgrade(
        Setup\ModuleDataSetupInterface $setup,
        Setup\ModuleContextInterface $moduleContext
    ) {
        $setup->startSetup();
        $eavSetup = $this->_eavSetupFactory->create(['setup' => $setup]);
        $eavSetup->updateAttribute(
            \Magento\Catalog\Model\Product::ENTITY,
            'your_attribute_code',
            'is_global', \Magento\Eav\Model\Entity\Attribute\ScopedAttributeInterface::SCOPE_GLOBAL
        );
        $setup->endSetup();
    }
}

Now, you have to update the version of the module from the module.xml file.

2nd Method: Using Data Patch

In this method, we need to create a data patch file as UpdateAttributes.php in our custom module Setup folder. Note: You can also use the different file names and class names.
complete path: app/code/ModuleNameSpace/YourModuleName/Setup/Patch/Data/UpdateAttributes.php

To learn more about data and schema patches, click here.

<?php

namespace ModuleNameSpace\YourModuleName\Setup\Patch\Data;

use Magento\Eav\Setup\EavSetupFactory;
use Magento\Framework\Setup\ModuleDataSetupInterface;
use Magento\Framework\Setup\Patch\DataPatchInterface;

class UpdateAttributes implements DataPatchInterface
{
    /**
     * @var ModuleDataSetupInterface
     */
    private $moduleDataSetup;
    /**
     * @var EavSetupFactory
     */
    private $eavSetupFactory;

    /**
     * @param ModuleDataSetupInterface $moduleDataSetup
     * @param EavSetupFactory $eavSetupFactory
     */
    public function __construct(
        ModuleDataSetupInterface $moduleDataSetup,
        EavSetupFactory $eavSetupFactory
    ) {
        $this->moduleDataSetup = $moduleDataSetup;
        $this->eavSetupFactory = $eavSetupFactory;
    }

    /**
     * Add eav attributes
     */
    public function apply()
    {
        /** @var EavSetup $eavSetup */
        $eavSetup = $this->eavSetupFactory->create(['setup' => $this->moduleDataSetup]);

        $eavSetup->updateAttribute(
            \Magento\Catalog\Model\Product::ENTITY,
            'your_attribute_code',
            'is_global',
\Magento\Eav\Model\Entity\Attribute\ScopedAttributeInterface::SCOPE_GLOBAL
        );
    }

    /**
     * Get dependencies
     */
    public static function getDependencies()
    {
        return [];
    }

    /**
     * Get Aliases
     */
    public function getAliases()
    {
        return [];
    }
}

After adding these files, update your custom product attribute’s scope in your custom module in your Magento 2 instance by running the following command in your magento2 root directory through the terminal.

php bin/magento setup:upgrade

now, the scope of the attribute changes to the Global

‘is_global’ flag is used instead of ‘global’ in updating the scope of an attribute.

Hope it will help you. Thank you.