MAGETWO-90684: Upgrade fails if DB contains view

Author: Sergii Kovalenko

lib/internal/Magento/Framework/Setup/Declaration/Schema/Db/MySQL/DbSchemaReader.php

@@ -17,6 +17,11 @@
  */
 class DbSchemaReader implements DbSchemaReaderInterface
 {
+    /**
+     * Table type in information_schema.TABLES which allows to identify only tables and ignore views
+     */
+    const MYSQL_TABLE_TYPE = 'BASE TABLE';
+
     /**
      * @var ResourceConnection
      */
@@ -209,8 +214,15 @@ public function readConstraints($tableName, $resource)
      */
     public function readTables($resource)
     {
-        return $this->resourceConnection
-            ->getConnection($resource)
-            ->getTables();
+        $adapter = $this->resourceConnection->getConnection($resource);
+        $dbName = $this->resourceConnection->getSchemaName($resource);
+        $stmt = $adapter->select()
+            ->from(
+                ['information_schema.TABLES'],
+                ['TABLE_NAME']
+            )
+            ->where('TABLE_SCHEMA = ?', $dbName)
+            ->where('TABLE_TYPE = ?', self::MYSQL_TABLE_TYPE);
+        return $adapter->fetchCol($stmt);
     }
 }