Fix multiselect with a lot of options not saved to DB

app/code/Magento/Catalog/Model/ResourceModel/Product/Indexer/Eav/Source.php

@@ -105,7 +105,7 @@ protected function _getIndexableAttributes($multiSelect)
         );
 
         if ($multiSelect == true) {
-            $select->where('ea.backend_type = ?', 'varchar')->where('ea.frontend_input = ?', 'multiselect');
+            $select->where('ea.backend_type = ?', 'text')->where('ea.frontend_input = ?', 'multiselect');
         } else {
             $select->where('ea.backend_type = ?', 'int')->where('ea.frontend_input IN( ? )', ['select', 'boolean']);
         }
@@ -303,14 +303,14 @@ protected function _prepareMultiselectIndex($entityIds = null, $attributeId = nu
         // prepare get multiselect values query
         $productValueExpression = $connection->getCheckSql('pvs.value_id > 0', 'pvs.value', 'pvd.value');
         $select = $connection->select()->from(
-            ['pvd' => $this->getTable('catalog_product_entity_varchar')],
+            ['pvd' => $this->getTable('catalog_product_entity_text')],
             []
         )->join(
             ['cs' => $this->getTable('store')],
             '',
             []
         )->joinLeft(
-            ['pvs' => $this->getTable('catalog_product_entity_varchar')],
+            ['pvs' => $this->getTable('catalog_product_entity_text')],
             "pvs.{$productIdField} = pvd.{$productIdField} AND pvs.attribute_id = pvd.attribute_id"
             . ' AND pvs.store_id=cs.store_id',
             []

app/code/Magento/Catalog/Setup/Patch/Data/UpdateMultiselectAttributesBackendTypes.php

@@ -0,0 +1,102 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+
+namespace Magento\Catalog\Setup\Patch\Data;
+
+use Magento\Catalog\Model\Product;
+use Magento\Eav\Setup\EavSetup;
+use Magento\Eav\Setup\EavSetupFactory;
+use Magento\Framework\Exception\LocalizedException;
+use Magento\Framework\Setup\ModuleDataSetupInterface;
+use Magento\Framework\Setup\Patch\DataPatchInterface;
+
+class UpdateMultiselectAttributesBackendTypes implements DataPatchInterface
+{
+    /**
+     * @var ModuleDataSetupInterface
+     */
+    private $dataSetup;
+    /**
+     * @var EavSetupFactory
+     */
+    private $eavSetupFactory;
+
+    /**
+     * MigrateMultiselectAttributesData constructor.
+     * @param ModuleDataSetupInterface $dataSetup
+     * @param EavSetupFactory $eavSetupFactory
+     */
+    public function __construct(
+        ModuleDataSetupInterface $dataSetup,
+        EavSetupFactory $eavSetupFactory
+    ) {
+        $this->dataSetup = $dataSetup;
+        $this->eavSetupFactory = $eavSetupFactory;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public static function getDependencies()
+    {
+        return [];
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getAliases()
+    {
+        return [];
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function apply()
+    {
+        $this->dataSetup->startSetup();
+
+        $connection = $this->dataSetup->getConnection();
+        $attributeTable = $connection->getTableName('eav_attribute');
+        /** @var EavSetup $eavSetup */
+        $eavSetup = $this->eavSetupFactory->create(['setup' => $this->dataSetup]);
+        $entityTypeId = $eavSetup->getEntityTypeId(Product::ENTITY);
+        $attributesToMigrate = $connection->fetchCol(
+            $connection
+                ->select()
+                ->from($attributeTable, ['attribute_id'])
+                ->where('entity_type_id = ?', $entityTypeId)
+                ->where('backend_type = ?', 'varchar')
+                ->where('frontend_input = ?', 'multiselect')
+        );
+
+        $varcharTable = $connection->getTableName('catalog_product_entity_varchar');
+        $textTable = $connection->getTableName('catalog_product_entity_text');
+        $varcharTableDataSql = $connection
+            ->select()
+            ->from($varcharTable)
+            ->where('attribute_id in (?)', $attributesToMigrate);
+        $dataToMigrate = array_map(static function ($row) {
+            $row['value_id'] = null;
+            return $row;
+        }, $connection->fetchAll($varcharTableDataSql));
+
+        foreach (array_chunk($dataToMigrate, 2000) as $dataChunk) {
+            $connection->insertMultiple($textTable, $dataChunk);
+        }
+
+        $connection->query($connection->deleteFromSelect($varcharTableDataSql, $varcharTable));
+
+        foreach ($attributesToMigrate as $attributeId) {
+            $eavSetup->updateAttribute($entityTypeId, $attributeId, 'backend_type', 'text');
+        }
+
+        $this->dataSetup->endSetup();
+
+        return $this;
+    }
+}

app/code/Magento/CatalogWidget/Model/Rule/Condition/Product.php

@@ -182,7 +182,7 @@ protected function addGlobalAttribute(
                 $linkField = $attribute->getEntity()->getLinkField();
 
                 $collection->getSelect()->join(
-                    [$alias => $collection->getTable('catalog_product_entity_varchar')],
+                    [$alias => $collection->getTable($attribute->getBackendTable())],
                     "($alias.$linkField = e.$linkField) AND ($alias.store_id = $storeId)" .
                     " AND ($alias.attribute_id = {$attribute->getId()})",
                     []

app/code/Magento/Eav/Model/Entity/Attribute.php

@@ -356,12 +356,12 @@ public function getBackendTypeByInput($type)
             case 'text':
             case 'gallery':
             case 'media_image':
-            case 'multiselect':
                 $field = 'varchar';
                 break;
 
             case 'image':
             case 'textarea':
+            case 'multiselect':
                 $field = 'text';
                 break;
 

app/code/Magento/Eav/Model/ResourceModel/Entity/Attribute.php

@@ -523,7 +523,7 @@ private function clearSelectedOptionInEntities(AbstractModel $object, int $optio
         $where = $connection->quoteInto('attribute_id = ?', $attributeId);
         $update = [];
 
-        if ($object->getBackendType() === 'varchar') {
+        if ($object->getBackendType() === 'text') {
             $where.= ' AND ' . $connection->prepareSqlCondition('value', ['finset' => $optionId]);
             $concat = $connection->getConcatSql(["','", 'value', "','"]);
             $expr = $connection->quoteInto(

app/code/Magento/Eav/Test/Unit/Model/Entity/AttributeTest.php

@@ -62,7 +62,7 @@ public static function dataGetBackendTypeByInput()
             ['text', 'varchar'],
             ['gallery', 'varchar'],
             ['media_image', 'varchar'],
-            ['multiselect', 'varchar'],
+            ['multiselect', 'text'],
             ['image', 'text'],
             ['textarea', 'text'],
             ['date', 'datetime'],

dev/tests/integration/framework/Magento/TestFramework/Eav/Model/Attribute/DataProvider/MultipleSelect.php

@@ -89,7 +89,7 @@ protected function getUpdateExpectedData(): array
                 'frontend_class' => null,
                 'used_for_sort_by' => '0',
                 'is_user_defined' => '1',
-                'backend_type' => 'varchar',
+                'backend_type' => 'text',
             ]
         );
     }

dev/tests/integration/testsuite/Magento/Catalog/Model/ProductGettersTest.php

@@ -225,6 +225,25 @@ public function testGetAttributeTextArray()
         );
     }
 
+    /**
+     * @magentoDataFixture Magento/Catalog/_files/products_with_multiselect_attribute.php
+     */
+    public function testMultipleMultiselectTextValues()
+    {
+        $expectedArray = [];
+
+        for ($i = 1; $i < 200; $i++) {
+            $expectedArray[] = sprintf('Multiselect option %d', $i);
+        }
+
+        $product = $this->productRepository->get('simple_ms_3');
+
+        self::assertEquals(
+            $expectedArray,
+            $product->getAttributeText('multiselect_attribute_text')
+        );
+    }
+
     public function testGetCustomDesignDate()
     {
         $this->assertEquals(['from' => null, 'to' => null], $this->_model->getCustomDesignDate());

dev/tests/integration/testsuite/Magento/Catalog/Model/ResourceModel/Product/Indexer/Eav/SourceTest.php

@@ -15,7 +15,6 @@
 use Magento\Store\Api\Data\StoreInterface;
 
 /**
- * Class SourceTest
  * @magentoAppIsolation enabled
  * @SuppressWarnings(PHPMD.CouplingBetweenObjects)
  */
@@ -69,7 +68,7 @@ public function testReindexEntitiesForConfigurableProduct()
 
         /** @var \Magento\Catalog\Model\ResourceModel\Eav\Attribute $attr **/
         $attr = Bootstrap::getObjectManager()->get(\Magento\Eav\Model\Config::class)
-           ->getAttribute('catalog_product', 'test_configurable');
+            ->getAttribute('catalog_product', 'test_configurable');
         $attr->setIsFilterable(1)->save();
 
         $this->_eavIndexerProcessor->reindexAll();
@@ -133,7 +132,7 @@ public function testReindexMultiselectAttribute()
 
         /** @var \Magento\Catalog\Model\ResourceModel\Eav\Attribute $attr **/
         $attr = $objectManager->get(\Magento\Eav\Model\Config::class)
-           ->getAttribute('catalog_product', 'multiselect_attribute');
+            ->getAttribute('catalog_product', 'multiselect_attribute');
 
         /** @var $options \Magento\Eav\Model\ResourceModel\Entity\Attribute\Option\Collection */
         $options = $objectManager->create(\Magento\Eav\Model\ResourceModel\Entity\Attribute\Option\Collection::class);
@@ -213,7 +212,7 @@ public function testReindexMultiselectAttributeWithSourceModel()
 
         /** @var \Magento\Catalog\Model\ResourceModel\Eav\Attribute $attr **/
         $attr = $objectManager->get(\Magento\Eav\Model\Config::class)
-           ->getAttribute('catalog_product', 'multiselect_attr_with_source');
+            ->getAttribute('catalog_product', 'multiselect_attr_with_source');
 
         /** @var $sourceModel MultiselectSourceMock */
         $sourceModel = \Magento\TestFramework\Helper\Bootstrap::getObjectManager()->create(
@@ -231,8 +230,8 @@ public function testReindexMultiselectAttributeWithSourceModel()
 
         /** @var \Magento\Catalog\Model\Product $product2 **/
         $product2 = $productRepository->getById($product2Id);
-        $product1->setSpecialFromDate(date('Y-m-d H:i:s'));
-        $product1->setNewsFromDate(date('Y-m-d H:i:s'));
+        $product2->setSpecialFromDate(date('Y-m-d H:i:s'));
+        $product2->setNewsFromDate(date('Y-m-d H:i:s'));
         $productRepository->save($product2);
 
         $this->_eavIndexerProcessor->reindexAll();

dev/tests/integration/testsuite/Magento/Catalog/_files/multiselect_attribute.php

@@ -8,13 +8,27 @@
 $installer = \Magento\TestFramework\Helper\Bootstrap::getObjectManager()->create(
     \Magento\Catalog\Setup\CategorySetup::class
 );
-/** @var $attribute \Magento\Catalog\Model\ResourceModel\Eav\Attribute */
-$attribute = \Magento\TestFramework\Helper\Bootstrap::getObjectManager()->create(
+/** @var $attributeMultiselect \Magento\Catalog\Model\ResourceModel\Eav\Attribute */
+$attributeMultiselect = \Magento\TestFramework\Helper\Bootstrap::getObjectManager()->create(
     \Magento\Catalog\Model\ResourceModel\Eav\Attribute::class
 );
+
+/** @var $attributeMultiselectText \Magento\Catalog\Model\ResourceModel\Eav\Attribute */
+$attributeMultiselectText = \Magento\TestFramework\Helper\Bootstrap::getObjectManager()->create(
+    \Magento\Catalog\Model\ResourceModel\Eav\Attribute::class
+);
+
+$valueOptionArray = [];
+$orderArray = [];
+
+for ($i = 1; $i < 200; $i++) {
+    $valueOptionArray[sprintf('option_%d', $i)] = [sprintf('Multiselect option %d', $i)];
+    $orderArray[sprintf('option_%d', $i)] = $i;
+}
+
 $entityType = $installer->getEntityTypeId('catalog_product');
-if (!$attribute->loadByCode($entityType, 'multiselect_attribute')->getAttributeId()) {
-    $attribute->setData(
+if (!$attributeMultiselect->loadByCode($entityType, 'multiselect_attribute')->getAttributeId()) {
+    $attributeMultiselect->setData(
         [
             'attribute_code' => 'multiselect_attribute',
             'entity_type_id' => $entityType,
@@ -34,7 +48,7 @@
             'used_in_product_listing' => 0,
             'used_for_sort_by' => 0,
             'frontend_label' => ['Multiselect Attribute'],
-            'backend_type' => 'varchar',
+            'backend_type' => 'text',
             'backend_model' => \Magento\Eav\Model\Entity\Attribute\Backend\ArrayBackend::class,
             'option' => [
                 'value' => [
@@ -52,8 +66,45 @@
             ],
         ]
     );
-    $attribute->save();
+    $attributeMultiselect->save();
+
+    /* Assign attribute to attribute set */
+    $installer->addAttributeToGroup('catalog_product', 'Default', 'General', $attributeMultiselect->getId());
+}
+
+
+if (!$attributeMultiselectText->loadByCode($entityType, 'multiselect_attribute_text')->getAttributeId()) {
+    $attributeMultiselectText->setData(
+        [
+            'attribute_code' => 'multiselect_attribute_text',
+            'entity_type_id' => $entityType,
+            'is_global' => 1,
+
+            'is_user_defined' => 1,
+            'frontend_input' => 'multiselect',
+            'is_unique' => 0,
+            'is_required' => 0,
+            'is_searchable' => 0,
+            'is_visible_in_advanced_search' => 0,
+            'is_comparable' => 0,
+            'is_filterable' => 1,
+            'is_filterable_in_search' => 0,
+            'is_used_for_promo_rules' => 0,
+            'is_html_allowed_on_front' => 1,
+            'is_visible_on_front' => 0,
+            'used_in_product_listing' => 0,
+            'used_for_sort_by' => 0,
+            'frontend_label' => ['Multiselect Attribute'],
+            'backend_type' => 'text',
+            'backend_model' => \Magento\Eav\Model\Entity\Attribute\Backend\ArrayBackend::class,
+            'option' => [
+                'value' => $valueOptionArray,
+                'order' => $orderArray
+            ],
+        ]
+    );
+    $attributeMultiselectText->save();
 
     /* Assign attribute to attribute set */
-    $installer->addAttributeToGroup('catalog_product', 'Default', 'General', $attribute->getId());
+    $installer->addAttributeToGroup('catalog_product', 'Default', 'General', $attributeMultiselectText->getId());
 }

dev/tests/integration/testsuite/Magento/Catalog/_files/multiselect_attribute_rollback.php

@@ -14,5 +14,8 @@
 $attribute->load('multiselect_attribute', 'attribute_code');
 $attribute->delete();
 
+$attribute->load('multiselect_attribute_text', 'attribute_code');
+$attribute->delete();
+
 $registry->unregister('isSecureArea');
 $registry->register('isSecureArea', false);

dev/tests/integration/testsuite/Magento/Catalog/_files/multiselect_attribute_with_html.php

@@ -41,7 +41,7 @@
             'used_in_product_listing' => 0,
             'used_for_sort_by' => 0,
             'frontend_label' => ['Multiselect Attribute'],
-            'backend_type' => 'varchar',
+            'backend_type' => 'text',
             'backend_model' => ArrayBackend::class,
             'option' => [
                 'value' => [

dev/tests/integration/testsuite/Magento/Catalog/_files/multiselect_attribute_with_incorrect_values.php

@@ -33,7 +33,7 @@
         'used_in_product_listing' => 0,
         'used_for_sort_by' => 0,
         'frontend_label' => ['Multiselect Attribute'],
-        'backend_type' => 'varchar',
+        'backend_type' => 'text',
         'backend_model' => \Magento\Eav\Model\Entity\Attribute\Backend\ArrayBackend::class,
         'option' => [
             'value' => [

dev/tests/integration/testsuite/Magento/Catalog/_files/multiselect_attribute_with_source_model.php

@@ -34,7 +34,7 @@
             'used_in_product_listing' => 0,
             'used_for_sort_by' => 0,
             'frontend_label' => ['Multiselect Attribute with Source Model'],
-            'backend_type' => 'varchar',
+            'backend_type' => 'text',
             'backend_model' => \Magento\Eav\Model\Entity\Attribute\Backend\ArrayBackend::class,
             'source_model' => \Magento\Catalog\_files\MultiselectSourceMock::class
         ]