diff --git a/dbms/src/Databases/DatabaseDictionary.cpp b/dbms/src/Databases/DatabaseDictionary.cpp
index 0dc471c9e0a..f41b23c9008 100644
--- a/dbms/src/Databases/DatabaseDictionary.cpp
+++ b/dbms/src/Databases/DatabaseDictionary.cpp
@@ -27,7 +27,7 @@ void DatabaseDictionary::loadTables(Context & context, ThreadPool * thread_pool,
 Tables DatabaseDictionary::loadTables()
 {
     auto objects_map = external_dictionaries.getObjectsMap();
-    const auto & dictionaries = std::get<1>(objects_map);
+    const auto & dictionaries = objects_map.get();
 
     Tables tables;
     for (const auto & pair : dictionaries)
@@ -52,7 +52,7 @@ bool DatabaseDictionary::isTableExist(
     const String & table_name) const
 {
     auto objects_map = external_dictionaries.getObjectsMap();
-    const auto & dictionaries = std::get<1>(objects_map);
+    const auto & dictionaries = objects_map.get();
     return dictionaries.count(table_name) && !deleted_tables.count(table_name);
 }
 
@@ -61,7 +61,7 @@ StoragePtr DatabaseDictionary::tryGetTable(
     const String & table_name)
 {
     auto objects_map = external_dictionaries.getObjectsMap();
-    const auto & dictionaries = std::get<1>(objects_map);
+    const auto & dictionaries = objects_map.get();
 
     if (deleted_tables.count(table_name))
         return {};
@@ -90,7 +90,7 @@ DatabaseIteratorPtr DatabaseDictionary::getIterator(const Context & context)
 bool DatabaseDictionary::empty(const Context & context) const
 {
     auto objects_map = external_dictionaries.getObjectsMap();
-    const auto & dictionaries = std::get<1>(objects_map);
+    const auto & dictionaries = objects_map.get();
     for (const auto & pair : dictionaries)
         if (pair.second.loadable && !deleted_tables.count(pair.first))
             return false;
diff --git a/dbms/src/Interpreters/ExternalLoader.cpp b/dbms/src/Interpreters/ExternalLoader.cpp
index 3bde003771b..3515ec6b2cd 100644
--- a/dbms/src/Interpreters/ExternalLoader.cpp
+++ b/dbms/src/Interpreters/ExternalLoader.cpp
@@ -425,9 +425,9 @@ ExternalLoader::LoadablePtr ExternalLoader::getLoadable(const std::string & name
     return it->second.loadable;
 }
 
-std::tuple<std::unique_lock<std::mutex>, const ExternalLoader::ObjectsMap &> ExternalLoader::getObjectsMap() const
+ExternalLoader::LockedObjectsMap ExternalLoader::getObjectsMap() const
 {
-    return std::make_tuple(std::unique_lock<std::mutex>(map_mutex), std::cref(loadable_objects));
+    return LockedObjectsMap(map_mutex, loadable_objects);
 }
 
 }
diff --git a/dbms/src/Interpreters/ExternalLoader.h b/dbms/src/Interpreters/ExternalLoader.h
index 672c801424e..d42e9f07877 100644
--- a/dbms/src/Interpreters/ExternalLoader.h
+++ b/dbms/src/Interpreters/ExternalLoader.h
@@ -101,8 +101,18 @@ protected:
     virtual std::unique_ptr<IExternalLoadable> create(const std::string & name, const Configuration & config,
                                                       const std::string & config_prefix) = 0;
 
+    class LockedObjectsMap
+    {
+    public:
+        LockedObjectsMap(std::mutex & mutex, const ObjectsMap & objectsMap) : lock(mutex), objectsMap(objectsMap) {}
+        const ObjectsMap & get() { return objectsMap; }
+    private:
+        std::unique_lock<std::mutex> lock;
+        const ObjectsMap & objectsMap;
+    };
+
     /// Direct access to objects.
-    std::tuple<std::unique_lock<std::mutex>, const ObjectsMap &> getObjectsMap() const;
+    LockedObjectsMap getObjectsMap() const;
 
     /// Should be called in derived constructor (to avoid pure virtual call).
     void init(bool throw_on_error);
diff --git a/dbms/src/Storages/System/StorageSystemDictionaries.cpp b/dbms/src/Storages/System/StorageSystemDictionaries.cpp
index 02a8c7a44aa..64d633d2d6b 100644
--- a/dbms/src/Storages/System/StorageSystemDictionaries.cpp
+++ b/dbms/src/Storages/System/StorageSystemDictionaries.cpp
@@ -77,7 +77,7 @@ BlockInputStreams StorageSystemDictionaries::read(
 
     const auto & external_dictionaries = context.getExternalDictionaries();
     auto objects_map = external_dictionaries.getObjectsMap();
-    const auto & dictionaries = std::get<1>(objects_map);
+    const auto & dictionaries = objects_map.get();
 
     for (const auto & dict_info : dictionaries)
     {