MC-37630: Updating Design Configuration runs full reindex which generates DDL statement DROP Table

Author: thiaramus

app/code/Magento/Theme/Model/Indexer/Design/Config.php

@@ -5,7 +5,6 @@
  */
 namespace Magento\Theme\Model\Indexer\Design;
 
-use Magento\Framework\App\ObjectManager;
 use Magento\Framework\Indexer\ActionInterface;
 use Magento\Framework\Indexer\FieldsetPool;
 use Magento\Framework\Indexer\HandlerPool;
@@ -94,30 +93,13 @@ protected function execute(array $ids = [])
         /** @var \Magento\Theme\Model\ResourceModel\Design\Config\Scope\Collection $collection */
         $collection = $this->collectionFactory->create();
         $this->prepareFields();
-
-        $tmp = $this->isFlatTableExists();
-
-        if (!$this->isFlatTableExists()) {
-            // instead of clean index check if table exists and create it if not
+        if (!count($ids)) {
             $this->getSaveHandler()->cleanIndex([]);
         }
         $this->getSaveHandler()->deleteIndex([], new \ArrayObject($ids));
         $this->getSaveHandler()->saveIndex([], $collection);
     }
 
-    private function isFlatTableExists()
-    {
-        /** @var \Magento\Framework\App\ResourceConnection $resource */
-        $resource = ObjectManager::getInstance()->get(\Magento\Framework\App\ResourceConnection::class);
-
-        /** @var \Magento\Framework\DB\Adapter\AdapterInterface $connection */
-        $connection = ObjectManager::getInstance()->get(\Magento\Framework\App\ResourceConnection::class)->getConnection();
-
-        $tableName = $resource->getTableName('design_config_grid_flat');
-
-        return $connection->isTableExists($tableName);
-    }
-
     /**
      * Execute full indexation
      *

app/code/Magento/Theme/Model/Indexer/Design/IndexerHandler.php

@@ -44,16 +44,29 @@ public function __construct(
     }
 
     /**
-     * Clean index table by truncation
+     * @return bool
+     */
+    private function isFlatTableExists()
+    {
+        $adapter = $this->resource->getConnection('write');
+        $tableName = $this->flatScopeResolver->resolve($this->getIndexName(), []);
+
+        return $adapter->isTableExists($tableName);
+    }
+
+    /**
+     * Clean index table by deleting all records
      *
      * @inheritdoc
      */
     public function cleanIndex($dimensions)
     {
-        $adapter = $this->resource->getConnection('write');
-        $tableName = $this->flatScopeResolver->resolve($this->getIndexName(), $dimensions);
-        if ($adapter->isTableExists($tableName)) {
-            $adapter->truncateTable($tableName);
+        if ($this->isFlatTableExists()) {
+            $adapter = $this->resource->getConnection('write');
+            $tableName = $this->flatScopeResolver->resolve($this->getIndexName(), $dimensions);
+            $adapter->delete($tableName);
+        } else {
+            $this->indexStructure->create($this->getIndexName(), $this->fields, $dimensions);
         }
     }
 }

app/code/Magento/Theme/etc/indexer.xml

@@ -17,7 +17,7 @@
             <field name="store_group_id" xsi:type="filterable" dataType="int"/>
             <field name="store_id" xsi:type="filterable" dataType="int"/>
         </fieldset>
-        <saveHandler class="Magento\Framework\Indexer\SaveHandler\Grid"/>
+        <saveHandler class="Magento\Theme\Model\Indexer\Design\IndexerHandler"/>
         <structure class="Magento\Framework\Indexer\GridStructure"/>
     </indexer>
 </config>

lib/internal/Magento/Framework/Indexer/SaveHandler/Grid.php

@@ -69,16 +69,10 @@ protected function prepareFilterableFields(array $documents)
      */
     public function deleteIndex($dimensions, \Traversable $ids)
     {
-        if (!empty(iterator_to_array($ids))) {
-            foreach ($this->batch->getItems($ids, $this->batchSize) as $batchIds) {
-                $this->connection->delete(
-                    $this->getTableName('filterable', $dimensions),
-                    ['entity_id IN(?)' => $batchIds]
-                );
-            }
-        } else {
-            $this->connection->truncateTable(
-                $this->getTableName('filterable', $dimensions)
+        foreach ($this->batch->getItems($ids, $this->batchSize) as $batchIds) {
+            $this->connection->delete(
+                $this->getTableName('filterable', $dimensions),
+                ['entity_id IN(?)' => $batchIds]
             );
         }
     }