Show information about not loaded dictionaries in system.columns, system.tables

and in "SHOW TABLES" executed in any database with the "Dictionary" engine.

contrib/poco

@@ -1 +1 @@
-Subproject commit ddca76ba4956cb57150082394536cc43ff28f6fa
+Subproject commit 7d605a1ae5d878294f91f68feb62ae51e9a04426

src/Common/ErrorCodes.cpp

@@ -491,6 +491,7 @@ namespace ErrorCodes
     extern const int CANNOT_ASSIGN_ALTER = 517;
     extern const int CANNOT_COMMIT_OFFSET = 518;
     extern const int NO_REMOTE_SHARD_AVAILABLE = 519;
+    extern const int CANNOT_DETACH_DICTIONARY_AS_TABLE = 520;
 
     extern const int KEEPER_EXCEPTION = 999;
     extern const int POCO_EXCEPTION = 1000;

src/Databases/DatabaseDictionary.cpp

@@ -1,6 +1,7 @@
 #include <Databases/DatabaseDictionary.h>
 #include <Interpreters/Context.h>
 #include <Interpreters/ExternalDictionariesLoader.h>
+#include <Dictionaries/DictionaryStructure.h>
 #include <Storages/StorageDictionary.h>
 #include <common/logger_useful.h>
 #include <IO/WriteBufferFromString.h>
@@ -15,6 +16,18 @@ namespace DB
 namespace ErrorCodes
 {
     extern const int SYNTAX_ERROR;
+    extern const int CANNOT_GET_CREATE_DICTIONARY_QUERY;
+}
+
+namespace
+{
+    StoragePtr createStorageDictionary(const String & database_name, const ExternalLoader::LoadResult & load_result)
+    {
+        if (!load_result.config)
+            return nullptr;
+        DictionaryStructure dictionary_structure = ExternalDictionariesLoader::getDictionaryStructure(*load_result.config);
+        return StorageDictionary::create(StorageID(database_name, load_result.name), load_result.name, dictionary_structure);
+    }
 }
 
 DatabaseDictionary::DatabaseDictionary(const String & name_)
@@ -26,29 +39,12 @@ DatabaseDictionary::DatabaseDictionary(const String & name_)
 Tables DatabaseDictionary::listTables(const Context & context, const FilterByNameFunction & filter_by_name)
 {
     Tables tables;
-    ExternalLoader::LoadResults load_results;
+    auto load_results = context.getExternalDictionariesLoader().getLoadResults(filter_by_name);
-    if (filter_by_name)
+    for (auto & load_result : load_results)
     {
-        /// If `filter_by_name` is set, we iterate through all dictionaries with such names. That's why we need to load all of them.
+        auto storage = createStorageDictionary(getDatabaseName(), load_result);
-        load_results = context.getExternalDictionariesLoader().tryLoad<ExternalLoader::LoadResults>(filter_by_name);
+        if (storage)
-    }
+            tables.emplace(storage->getStorageID().table_name, storage);
-    else
-    {
-        /// If `filter_by_name` isn't set, we iterate through only already loaded dictionaries. We don't try to load all dictionaries in this case.
-        load_results = context.getExternalDictionariesLoader().getCurrentLoadResults();
-    }
-
-    for (const auto & load_result: load_results)
-    {
-        /// Load tables only from XML dictionaries, don't touch other
-        if (load_result.object && load_result.repository_name.empty())
-        {
-            auto dict_ptr = std::static_pointer_cast<const IDictionaryBase>(load_result.object);
-            auto dict_name = dict_ptr->getName();
-            const DictionaryStructure & dictionary_structure = dict_ptr->getStructure();
-            auto columns = StorageDictionary::getNamesAndTypes(dictionary_structure);
-            tables[dict_name] = StorageDictionary::create(StorageID(getDatabaseName(), dict_name), ColumnsDescription{columns}, context, true, dict_name);
-        }
     }
     return tables;
 }
@@ -64,15 +60,8 @@ StoragePtr DatabaseDictionary::tryGetTable(
     const Context & context,
     const String & table_name) const
 {
-    auto dict_ptr = context.getExternalDictionariesLoader().tryGetDictionary(table_name, true /*load*/);
+    auto load_result = context.getExternalDictionariesLoader().getLoadResult(table_name);
-    if (dict_ptr)
+    return createStorageDictionary(getDatabaseName(), load_result);
-    {
-        const DictionaryStructure & dictionary_structure = dict_ptr->getStructure();
-        auto columns = StorageDictionary::getNamesAndTypes(dictionary_structure);
-        return StorageDictionary::create(StorageID(getDatabaseName(), table_name), ColumnsDescription{columns}, context, true, table_name);
-    }
-
-    return {};
 }
 
 DatabaseTablesIteratorPtr DatabaseDictionary::getTablesIterator(const Context & context, const FilterByNameFunction & filter_by_table_name)
@@ -82,7 +71,7 @@ DatabaseTablesIteratorPtr DatabaseDictionary::getTablesIterator(const Context &
 
 bool DatabaseDictionary::empty(const Context & context) const
 {
-    return !context.getExternalDictionariesLoader().hasCurrentlyLoadedObjects();
+    return !context.getExternalDictionariesLoader().hasObjects();
 }
 
 ASTPtr DatabaseDictionary::getCreateTableQueryImpl(const Context & context,
@@ -92,15 +81,17 @@ ASTPtr DatabaseDictionary::getCreateTableQueryImpl(const Context & context,
     {
         WriteBufferFromString buffer(query);
 
-        const auto & dictionaries = context.getExternalDictionariesLoader();
+        auto load_result = context.getExternalDictionariesLoader().getLoadResult(table_name);
-        auto dictionary = throw_on_error ? dictionaries.getDictionary(table_name)
+        if (!load_result.config)
-                                         : dictionaries.tryGetDictionary(table_name, true /*load*/);
+        {
-        if (!dictionary)
+            if (throw_on_error)
+                throw Exception{"Dictionary " + backQuote(table_name) + " doesn't exist", ErrorCodes::CANNOT_GET_CREATE_DICTIONARY_QUERY};
             return {};
+        }
 
-        auto names_and_types = StorageDictionary::getNamesAndTypes(dictionary->getStructure());
+        auto names_and_types = StorageDictionary::getNamesAndTypes(ExternalDictionariesLoader::getDictionaryStructure(*load_result.config));
         buffer << "CREATE TABLE " << backQuoteIfNeed(database_name) << '.' << backQuoteIfNeed(table_name) << " (";
-        buffer << StorageDictionary::generateNamesAndTypesDescription(names_and_types.begin(), names_and_types.end());
+        buffer << StorageDictionary::generateNamesAndTypesDescription(names_and_types);
         buffer << ") Engine = Dictionary(" << backQuoteIfNeed(table_name) << ")";
     }
 

src/Databases/DatabaseDictionary.h

@@ -43,6 +43,8 @@ public:
 
     ASTPtr getCreateDatabaseQuery(const Context & context) const override;
 
+    bool shouldBeEmptyOnDetach() const override { return false; }
+
     void shutdown() override;
 
 protected:

src/Databases/DatabaseOrdinary.cpp

@@ -16,6 +16,7 @@
 #include <Parsers/parseQuery.h>
 #include <Parsers/formatAST.h>
 #include <Parsers/ASTSetQuery.h>
+#include <Dictionaries/getDictionaryConfigurationFromAST.h>
 #include <TableFunctions/TableFunctionFactory.h>
 
 #include <Parsers/queryToString.h>
@@ -74,18 +75,24 @@ namespace
 
 
     void tryAttachDictionary(
-        Context & context,
+        const ASTPtr & query,
-        const ASTCreateQuery & query,
+        DatabaseOrdinary & database,
-        DatabaseOrdinary & database)
+        const String & metadata_path)
     {
-        assert(query.is_dictionary);
+        auto & create_query = query->as<ASTCreateQuery &>();
+        assert(create_query.is_dictionary);
         try
         {
-            database.attachDictionary(query.table, context);
+            Poco::File meta_file(metadata_path);
+            auto config = getDictionaryConfigurationFromAST(create_query);
+            time_t modification_time = meta_file.getLastModified().epochTime();
+            database.attachDictionary(create_query.table, DictionaryAttachInfo{query, config, modification_time});
         }
         catch (Exception & e)
         {
-            e.addMessage("Cannot attach table '" + backQuote(query.table) + "' from query " + serializeAST(query));
+            e.addMessage("Cannot attach dictionary " + backQuote(database.getDatabaseName()) + "." + backQuote(create_query.table) +
+                         " from metadata file " + metadata_path +
+                         " from query " + serializeAST(*query));
             throw;
         }
     }
@@ -173,12 +180,12 @@ void DatabaseOrdinary::loadStoredObjects(
 
     /// Attach dictionaries.
     attachToExternalDictionariesLoader(context);
-    for (const auto & name_with_query : file_names)
+    for (const auto & [name, query] : file_names)
     {
-        auto create_query = name_with_query.second->as<const ASTCreateQuery &>();
+        auto create_query = query->as<const ASTCreateQuery &>();
         if (create_query.is_dictionary)
         {
-            tryAttachDictionary(context, create_query, *this);
+            tryAttachDictionary(query, *this, getMetadataPath() + name);
 
             /// Messages, so that it's not boring to wait for the server to load for a long time.
             logAboutProgress(log, ++dictionaries_processed, total_dictionaries, watch);

src/Databases/DatabaseWithDictionaries.cpp

@@ -5,6 +5,8 @@
 #include <Interpreters/ExternalLoaderTempConfigRepository.h>
 #include <Interpreters/ExternalLoaderDatabaseConfigRepository.h>
 #include <Dictionaries/getDictionaryConfigurationFromAST.h>
+#include <Dictionaries/DictionaryStructure.h>
+#include <Parsers/ASTCreateQuery.h>
 #include <Interpreters/Context.h>
 #include <Storages/StorageDictionary.h>
 #include <IO/WriteBufferFromFile.h>
@@ -24,46 +26,80 @@ namespace ErrorCodes
 {
     extern const int CANNOT_GET_CREATE_DICTIONARY_QUERY;
     extern const int TABLE_ALREADY_EXISTS;
-    extern const int UNKNOWN_TABLE;
+    extern const int UNKNOWN_DICTIONARY;
     extern const int DICTIONARY_ALREADY_EXISTS;
     extern const int FILE_DOESNT_EXIST;
-    extern const int CANNOT_GET_CREATE_TABLE_QUERY;
 }
 
 
-void DatabaseWithDictionaries::attachDictionary(const String & dictionary_name, const Context & context)
+void DatabaseWithDictionaries::attachDictionary(const String & dictionary_name, const DictionaryAttachInfo & attach_info)
 {
     String full_name = getDatabaseName() + "." + dictionary_name;
     {
         std::lock_guard lock(mutex);
-        if (!dictionaries.emplace(dictionary_name).second)
+        auto [it, inserted] = dictionaries.emplace(dictionary_name, attach_info);
+        if (!inserted)
             throw Exception("Dictionary " + full_name + " already exists.", ErrorCodes::DICTIONARY_ALREADY_EXISTS);
+
+        /// Attach the dictionary as table too.
+        try
+        {
+            attachTableUnlocked(
+                dictionary_name,
+                StorageDictionary::create(
+                    StorageID(getDatabaseName(), dictionary_name),
+                    full_name,
+                    ExternalDictionariesLoader::getDictionaryStructure(*attach_info.config)));
+        }
+        catch (...)
+        {
+            dictionaries.erase(it);
+            throw;
+        }
     }
 
     CurrentStatusInfo::set(CurrentStatusInfo::DictionaryStatus, full_name, static_cast<Int8>(ExternalLoaderStatus::NOT_LOADED));
+
     /// ExternalLoader::reloadConfig() will find out that the dictionary's config has been added
     /// and in case `dictionaries_lazy_load == false` it will load the dictionary.
-    const auto & external_loader = context.getExternalDictionariesLoader();
+    external_loader->reloadConfig(getDatabaseName(), full_name);
-    external_loader.reloadConfig(getDatabaseName(), full_name);
 }
 
-void DatabaseWithDictionaries::detachDictionary(const String & dictionary_name, const Context & context)
+void DatabaseWithDictionaries::detachDictionary(const String & dictionary_name)
+{
+    DictionaryAttachInfo attach_info;
+    detachDictionaryImpl(dictionary_name, attach_info);
+}
+
+void DatabaseWithDictionaries::detachDictionaryImpl(const String & dictionary_name, DictionaryAttachInfo & attach_info)
 {
     String full_name = getDatabaseName() + "." + dictionary_name;
+
     {
         std::lock_guard lock(mutex);
         auto it = dictionaries.find(dictionary_name);
         if (it == dictionaries.end())
-            throw Exception("Dictionary " + full_name + " doesn't exist.", ErrorCodes::UNKNOWN_TABLE);
+            throw Exception("Dictionary " + full_name + " doesn't exist.", ErrorCodes::UNKNOWN_DICTIONARY);
+        attach_info = std::move(it->second);
         dictionaries.erase(it);
+
+        /// Detach the dictionary as table too.
+        try
+        {
+            detachTableUnlocked(dictionary_name);
+        }
+        catch (...)
+        {
+            dictionaries.emplace(dictionary_name, std::move(attach_info));
+            throw;
+        }
     }
 
     CurrentStatusInfo::unset(CurrentStatusInfo::DictionaryStatus, full_name);
+
     /// ExternalLoader::reloadConfig() will find out that the dictionary's config has been removed
     /// and therefore it will unload the dictionary.
-    const auto & external_loader = context.getExternalDictionariesLoader();
+    external_loader->reloadConfig(getDatabaseName(), full_name);
-    external_loader.reloadConfig(getDatabaseName(), full_name);
-
 }
 
 void DatabaseWithDictionaries::createDictionary(const Context & context, const String & dictionary_name, const ASTPtr & query)
@@ -85,8 +121,7 @@ void DatabaseWithDictionaries::createDictionary(const Context & context, const S
 
     /// A dictionary with the same full name could be defined in *.xml config files.
     String full_name = getDatabaseName() + "." + dictionary_name;
-    const auto & external_loader = context.getExternalDictionariesLoader();
+    if (external_loader->getCurrentStatus(full_name) != ExternalLoader::Status::NOT_EXIST)
-    if (external_loader.getCurrentStatus(full_name) != ExternalLoader::Status::NOT_EXIST)
         throw Exception(
                 "Dictionary " + backQuote(getDatabaseName()) + "." + backQuote(dictionary_name) + " already exists.",
                 ErrorCodes::DICTIONARY_ALREADY_EXISTS);
@@ -117,23 +152,22 @@ void DatabaseWithDictionaries::createDictionary(const Context & context, const S
 
     /// Add a temporary repository containing the dictionary.
     /// We need this temp repository to try loading the dictionary before actually attaching it to the database.
-    auto temp_repository
+    auto temp_repository = external_loader->addConfigRepository(std::make_unique<ExternalLoaderTempConfigRepository>(
-        = const_cast<ExternalDictionariesLoader &>(external_loader) /// the change of ExternalDictionariesLoader is temporary
+        getDatabaseName(), dictionary_metadata_tmp_path, getDictionaryConfigurationFromAST(query->as<const ASTCreateQuery &>())));
-              .addConfigRepository(std::make_unique<ExternalLoaderTempConfigRepository>(
-                  getDatabaseName(), dictionary_metadata_tmp_path, getDictionaryConfigurationFromAST(query->as<const ASTCreateQuery &>())));
 
     bool lazy_load = context.getConfigRef().getBool("dictionaries_lazy_load", true);
     if (!lazy_load)
     {
         /// load() is called here to force loading the dictionary, wait until the loading is finished,
         /// and throw an exception if the loading is failed.
-        external_loader.load(full_name);
+        external_loader->load(full_name);
     }
 
-    attachDictionary(dictionary_name, context);
+    auto config = getDictionaryConfigurationFromAST(query->as<const ASTCreateQuery &>());
+    attachDictionary(dictionary_name, DictionaryAttachInfo{query, config, time(nullptr)});
     SCOPE_EXIT({
         if (!succeeded)
-            detachDictionary(dictionary_name, context);
+            detachDictionary(dictionary_name);
     });
 
     /// If it was ATTACH query and file with dictionary metadata already exist
@@ -142,94 +176,31 @@ void DatabaseWithDictionaries::createDictionary(const Context & context, const S
 
     /// ExternalDictionariesLoader doesn't know we renamed the metadata path.
     /// So we have to manually call reloadConfig() here.
-    external_loader.reloadConfig(getDatabaseName(), full_name);
+    external_loader->reloadConfig(getDatabaseName(), full_name);
 
     /// Everything's ok.
     succeeded = true;
 }
 
-void DatabaseWithDictionaries::removeDictionary(const Context & context, const String & dictionary_name)
+void DatabaseWithDictionaries::removeDictionary(const Context &, const String & dictionary_name)
 {
-    detachDictionary(dictionary_name, context);
+    DictionaryAttachInfo attach_info;
-
+    detachDictionaryImpl(dictionary_name, attach_info);
-    String dictionary_metadata_path = getObjectMetadataPath(dictionary_name);
 
     try
     {
+        String dictionary_metadata_path = getObjectMetadataPath(dictionary_name);
         Poco::File(dictionary_metadata_path).remove();
         CurrentStatusInfo::unset(CurrentStatusInfo::DictionaryStatus, getDatabaseName() + "." + dictionary_name);
     }
     catch (...)
     {
         /// If remove was not possible for some reason
-        attachDictionary(dictionary_name, context);
+        attachDictionary(dictionary_name, attach_info);
         throw;
     }
 }
 
-StoragePtr DatabaseWithDictionaries::tryGetTableImpl(const Context & context, const String & table_name, bool load) const
-{
-    if (auto table_ptr = DatabaseWithOwnTablesBase::tryGetTable(context, table_name))
-        return table_ptr;
-
-    if (isDictionaryExist(context, table_name))
-        /// We don't need lock database here, because database doesn't store dictionary itself
-        /// just metadata
-        return getDictionaryStorage(context, table_name, load);
-
-    return {};
-}
-StoragePtr DatabaseWithDictionaries::tryGetTable(const Context & context, const String & table_name) const
-{
-    return tryGetTableImpl(context, table_name, true /*load*/);
-}
-
-ASTPtr DatabaseWithDictionaries::getCreateTableQueryImpl(const Context & context, const String & table_name, bool throw_on_error) const
-{
-    ASTPtr ast;
-    bool has_table = tryGetTableImpl(context, table_name, false /*load*/) != nullptr;
-    auto table_metadata_path = getObjectMetadataPath(table_name);
-    try
-    {
-        ast = getCreateQueryFromMetadata(context, table_metadata_path, throw_on_error);
-    }
-    catch (const Exception & e)
-    {
-        if (!has_table && e.code() == ErrorCodes::FILE_DOESNT_EXIST && throw_on_error)
-            throw Exception{"Table " + backQuote(table_name) + " doesn't exist",
-                            ErrorCodes::CANNOT_GET_CREATE_TABLE_QUERY};
-        else if (throw_on_error)
-            throw;
-    }
-    return ast;
-}
-
-DatabaseTablesIteratorPtr DatabaseWithDictionaries::getTablesWithDictionaryTablesIterator(
-    const Context & context, const FilterByNameFunction & filter_by_dictionary_name)
-{
-    /// NOTE: it's not atomic
-    auto tables_it = getTablesIterator(context, filter_by_dictionary_name);
-    auto dictionaries_it = getDictionariesIterator(context, filter_by_dictionary_name);
-
-    Tables result;
-    while (tables_it && tables_it->isValid())
-    {
-        result.emplace(tables_it->name(), tables_it->table());
-        tables_it->next();
-    }
-
-    while (dictionaries_it && dictionaries_it->isValid())
-    {
-        auto table_name = dictionaries_it->name();
-        auto table_ptr = getDictionaryStorage(context, table_name, false /*load*/);
-        if (table_ptr)
-            result.emplace(table_name, table_ptr);
-        dictionaries_it->next();
-    }
-
-    return std::make_unique<DatabaseTablesSnapshotIterator>(result);
-}
-
 DatabaseDictionariesIteratorPtr DatabaseWithDictionaries::getDictionariesIterator(const Context & /*context*/, const FilterByNameFunction & filter_by_dictionary_name)
 {
     std::lock_guard lock(mutex);
@@ -237,9 +208,9 @@ DatabaseDictionariesIteratorPtr DatabaseWithDictionaries::getDictionariesIterato
         return std::make_unique<DatabaseDictionariesSnapshotIterator>(dictionaries);
 
     Dictionaries filtered_dictionaries;
-    for (const auto & dictionary_name : dictionaries)
+    for (const auto & dictionary_name : dictionaries | boost::adaptors::map_keys)
         if (filter_by_dictionary_name(dictionary_name))
-            filtered_dictionaries.emplace(dictionary_name);
+            filtered_dictionaries.emplace_back(dictionary_name);
     return std::make_unique<DatabaseDictionariesSnapshotIterator>(std::move(filtered_dictionaries));
 }
 
@@ -249,44 +220,84 @@ bool DatabaseWithDictionaries::isDictionaryExist(const Context & /*context*/, co
     return dictionaries.find(dictionary_name) != dictionaries.end();
 }
 
-StoragePtr DatabaseWithDictionaries::getDictionaryStorage(const Context & context, const String & table_name, bool load) const
-{
-    auto dict_name = database_name + "." + table_name;
-    const auto & external_loader = context.getExternalDictionariesLoader();
-    auto dict_ptr = external_loader.tryGetDictionary(dict_name, load);
-    if (dict_ptr)
-    {
-        const DictionaryStructure & dictionary_structure = dict_ptr->getStructure();
-        auto columns = StorageDictionary::getNamesAndTypes(dictionary_structure);
-        return StorageDictionary::create(StorageID(database_name, table_name), ColumnsDescription{columns}, context, true, dict_name);
-    }
-    return nullptr;
-}
-
 ASTPtr DatabaseWithDictionaries::getCreateDictionaryQueryImpl(
         const Context & context,
         const String & dictionary_name,
         bool throw_on_error) const
 {
-    ASTPtr ast;
-
-    auto dictionary_metadata_path = getObjectMetadataPath(dictionary_name);
-    ast = getCreateQueryFromMetadata(context, dictionary_metadata_path, throw_on_error);
-    if (!ast && throw_on_error)
     {
-        /// Handle system.* tables for which there are no table.sql files.
+        /// Try to get create query ifg for an attached dictionary.
-        bool has_dictionary = isDictionaryExist(context, dictionary_name);
+        std::lock_guard lock{mutex};
-
+        auto it = dictionaries.find(dictionary_name);
-        auto msg = has_dictionary ? "There is no CREATE DICTIONARY query for table " : "There is no metadata file for dictionary ";
+        if (it != dictionaries.end())
-
+        {
-        throw Exception(msg + backQuote(dictionary_name), ErrorCodes::CANNOT_GET_CREATE_DICTIONARY_QUERY);
+            ASTPtr ast = it->second.create_query->clone();
+            auto & create_query = ast->as<ASTCreateQuery &>();
+            create_query.attach = false;
+            create_query.database = getDatabaseName();
+            return ast;
+        }
     }
 
-    return ast;
+    /// Try to get create query for non-attached dictionary.
+    ASTPtr ast;
+    try
+    {
+        auto dictionary_metadata_path = getObjectMetadataPath(dictionary_name);
+        ast = getCreateQueryFromMetadata(context, dictionary_metadata_path, throw_on_error);
+    }
+    catch (const Exception & e)
+    {
+        if (throw_on_error && (e.code() != ErrorCodes::FILE_DOESNT_EXIST))
+            throw;
+    }
+
+    if (ast)
+    {
+        const auto * create_query = ast->as<const ASTCreateQuery>();
+        if (create_query && create_query->is_dictionary)
+            return ast;
+    }
+    if (throw_on_error)
+        throw Exception{"Dictionary " + backQuote(dictionary_name) + " doesn't exist",
+                        ErrorCodes::CANNOT_GET_CREATE_DICTIONARY_QUERY};
+    return nullptr;
+}
+
+
+Poco::AutoPtr<Poco::Util::AbstractConfiguration> DatabaseWithDictionaries::getDictionaryConfiguration(const String & dictionary_name) const
+{
+    std::lock_guard lock(mutex);
+    auto it = dictionaries.find(dictionary_name);
+    if (it != dictionaries.end())
+        return it->second.config;
+    throw Exception("Dictionary " + backQuote(dictionary_name) + " doesn't exist", ErrorCodes::UNKNOWN_DICTIONARY);
+}
+
+time_t DatabaseWithDictionaries::getObjectMetadataModificationTime(const String & object_name) const
+{
+    {
+        std::lock_guard lock(mutex);
+        auto it = dictionaries.find(object_name);
+        if (it != dictionaries.end())
+            return it->second.modification_time;
+    }
+    return DatabaseOnDisk::getObjectMetadataModificationTime(object_name);
+}
+
+
+bool DatabaseWithDictionaries::empty(const Context &) const
+{
+    std::lock_guard lock{mutex};
+    return tables.empty() && dictionaries.empty();
 }
 
 void DatabaseWithDictionaries::shutdown()
 {
+    {
+        std::lock_guard lock(mutex);
+        dictionaries.clear();
+    }
     detachFromExternalDictionariesLoader();
     DatabaseOnDisk::shutdown();
 }
@@ -295,8 +306,9 @@ DatabaseWithDictionaries::~DatabaseWithDictionaries() = default;
 
 void DatabaseWithDictionaries::attachToExternalDictionariesLoader(Context & context)
 {
-    database_as_config_repo_for_external_loader = context.getExternalDictionariesLoader().addConfigRepository(
+    external_loader = &context.getExternalDictionariesLoader();
-        std::make_unique<ExternalLoaderDatabaseConfigRepository>(*this, context));
+    database_as_config_repo_for_external_loader
+        = external_loader->addConfigRepository(std::make_unique<ExternalLoaderDatabaseConfigRepository>(*this, context));
 }
 
 void DatabaseWithDictionaries::detachFromExternalDictionariesLoader()

src/Databases/DatabaseWithDictionaries.h

@@ -8,9 +8,9 @@ namespace DB
 class DatabaseWithDictionaries : public DatabaseOnDisk
 {
 public:
-    void attachDictionary(const String & name, const Context & context) override;
+    void attachDictionary(const String & dictionary_name, const DictionaryAttachInfo & attach_info) override;
 
-    void detachDictionary(const String & name, const Context & context) override;
+    void detachDictionary(const String & dictionary_name) override;
 
     void createDictionary(const Context & context,
                           const String & dictionary_name,
@@ -18,15 +18,15 @@ public:
 
     void removeDictionary(const Context & context, const String & dictionary_name) override;
 
-    StoragePtr tryGetTable(const Context & context, const String & table_name) const override;
+    bool isDictionaryExist(const Context & context, const String & dictionary_name) const override;
-
-    ASTPtr getCreateTableQueryImpl(const Context & context, const String & table_name, bool throw_on_error) const override;
-
-    DatabaseTablesIteratorPtr getTablesWithDictionaryTablesIterator(const Context & context, const FilterByNameFunction & filter_by_dictionary_name) override;
 
     DatabaseDictionariesIteratorPtr getDictionariesIterator(const Context & context, const FilterByNameFunction & filter_by_dictionary_name) override;
 
-    bool isDictionaryExist(const Context & context, const String & dictionary_name) const override;
+    Poco::AutoPtr<Poco::Util::AbstractConfiguration> getDictionaryConfiguration(const String & /*name*/) const override;
+
+    time_t getObjectMetadataModificationTime(const String & object_name) const override;
+
+    bool empty(const Context & context) const override;
 
     void shutdown() override;
 
@@ -39,16 +39,17 @@ protected:
     void attachToExternalDictionariesLoader(Context & context);
     void detachFromExternalDictionariesLoader();
 
-    StoragePtr getDictionaryStorage(const Context & context, const String & table_name, bool load) const;
+    void detachDictionaryImpl(const String & dictionary_name, DictionaryAttachInfo & attach_info);
 
     ASTPtr getCreateDictionaryQueryImpl(const Context & context,
                                         const String & dictionary_name,
                                         bool throw_on_error) const override;
 
-private:
+    std::unordered_map<String, DictionaryAttachInfo> dictionaries;
-    ext::scope_guard database_as_config_repo_for_external_loader;
 
-    StoragePtr tryGetTableImpl(const Context & context, const String & table_name, bool load) const;
+private:
+    ExternalDictionariesLoader * external_loader = nullptr;
+    ext::scope_guard database_as_config_repo_for_external_loader;
 };
 
 }

src/Databases/DatabasesCommon.cpp

@@ -27,7 +27,7 @@ bool DatabaseWithOwnTablesBase::isTableExist(
     const String & table_name) const
 {
     std::lock_guard lock(mutex);
-    return tables.find(table_name) != tables.end() || dictionaries.find(table_name) != dictionaries.end();
+    return tables.find(table_name) != tables.end();
 }
 
 StoragePtr DatabaseWithOwnTablesBase::tryGetTable(
@@ -58,7 +58,7 @@ DatabaseTablesIteratorPtr DatabaseWithOwnTablesBase::getTablesIterator(const Con
 bool DatabaseWithOwnTablesBase::empty(const Context & /*context*/) const
 {
     std::lock_guard lock(mutex);
-    return tables.empty() && dictionaries.empty();
+    return tables.empty();
 }
 
 StoragePtr DatabaseWithOwnTablesBase::detachTable(const String & table_name)
@@ -125,7 +125,6 @@ void DatabaseWithOwnTablesBase::shutdown()
 
     std::lock_guard lock(mutex);
     tables.clear();
-    dictionaries.clear();
 }
 
 DatabaseWithOwnTablesBase::~DatabaseWithOwnTablesBase()

src/Databases/DatabasesCommon.h

@@ -42,7 +42,6 @@ public:
 protected:
     mutable std::mutex mutex;
     Tables tables;
-    Dictionaries dictionaries;
     Poco::Logger * log;
 
     DatabaseWithOwnTablesBase(const String & name_, const String & logger);

src/Databases/DictionaryAttachInfo.h

@@ -0,0 +1,18 @@
+#pragma once
+
+#include <Parsers/IAST_fwd.h>
+#include <Poco/AutoPtr.h>
+#include <Poco/Util/AbstractConfiguration.h>
+
+
+namespace DB
+{
+
+struct DictionaryAttachInfo
+{
+    ASTPtr create_query;
+    Poco::AutoPtr<Poco::Util::AbstractConfiguration> config;
+    time_t modification_time;
+};
+
+}

src/Databases/IDatabase.h

@@ -5,8 +5,11 @@
 #include <Storages/IStorage_fwd.h>
 #include <Storages/StorageInMemoryMetadata.h>
 #include <Dictionaries/IDictionary.h>
+#include <Databases/DictionaryAttachInfo.h>
 #include <Common/Exception.h>
 
+#include <boost/range/adaptor/map.hpp>
+#include <boost/range/algorithm/copy.hpp>
 #include <ctime>
 #include <functional>
 #include <memory>
@@ -18,11 +21,10 @@ namespace DB
 class Context;
 struct Settings;
 struct ConstraintsDescription;
-class ColumnsDescription;
 struct IndicesDescription;
 struct TableStructureWriteLockHolder;
 class ASTCreateQuery;
-using Dictionaries = std::set<String>;
+using Dictionaries = std::vector<String>;
 
 namespace ErrorCodes
 {
@@ -74,9 +76,14 @@ private:
 public:
     DatabaseDictionariesSnapshotIterator() = default;
     DatabaseDictionariesSnapshotIterator(Dictionaries & dictionaries_) : dictionaries(dictionaries_), it(dictionaries.begin()) {}
-
     DatabaseDictionariesSnapshotIterator(Dictionaries && dictionaries_) : dictionaries(dictionaries_), it(dictionaries.begin()) {}
 
+    DatabaseDictionariesSnapshotIterator(const std::unordered_map<String, DictionaryAttachInfo> & dictionaries_)
+    {
+        boost::range::copy(dictionaries_ | boost::adaptors::map_keys, std::back_inserter(dictionaries));
+        it = dictionaries.begin();
+    }
+
     void next() { ++it; }
 
     bool isValid() const { return !dictionaries.empty() && it != dictionaries.end(); }
@@ -140,12 +147,6 @@ public:
         return std::make_unique<DatabaseDictionariesSnapshotIterator>();
     }
 
-    /// Get an iterator to pass through all the tables and dictionary tables.
-    virtual DatabaseTablesIteratorPtr getTablesWithDictionaryTablesIterator(const Context & context, const FilterByNameFunction & filter_by_name = {})
-    {
-        return getTablesIterator(context, filter_by_name);
-    }
-
     /// Is the database empty.
     virtual bool empty(const Context & context) const = 0;
 
@@ -192,7 +193,7 @@ public:
 
     /// Add dictionary to the database, but do not add it to the metadata. The database may not support this method.
     /// If dictionaries_lazy_load is false it also starts loading the dictionary asynchronously.
-    virtual void attachDictionary(const String & /*name*/, const Context & /*context*/)
+    virtual void attachDictionary(const String & /* dictionary_name */, const DictionaryAttachInfo & /* attach_info */)
     {
         throw Exception("There is no ATTACH DICTIONARY query for Database" + getEngineName(), ErrorCodes::NOT_IMPLEMENTED);
     }
@@ -204,7 +205,7 @@ public:
     }
 
     /// Forget about the dictionary without deleting it. The database may not support this method.
-    virtual void detachDictionary(const String & /*name*/, const Context & /*context*/)
+    virtual void detachDictionary(const String & /*name*/)
     {
         throw Exception("There is no DETACH DICTIONARY query for Database" + getEngineName(), ErrorCodes::NOT_IMPLEMENTED);
     }
@@ -260,6 +261,11 @@ public:
         return getCreateDictionaryQueryImpl(context, name, true);
     }
 
+    virtual Poco::AutoPtr<Poco::Util::AbstractConfiguration> getDictionaryConfiguration(const String & /*name*/) const
+    {
+        throw Exception(getEngineName() + ": getDictionaryConfiguration() is not supported", ErrorCodes::NOT_IMPLEMENTED);
+    }
+
     /// Get the CREATE DATABASE query for current database.
     virtual ASTPtr getCreateDatabaseQuery(const Context & /*context*/) const = 0;
 
@@ -276,6 +282,9 @@ public:
     /// Returns metadata path of a concrete table if the database supports it, empty string otherwise
     virtual String getObjectMetadataPath(const String & /*table_name*/) const { return {}; }
 
+    /// All tables and dictionaries should be detached before detaching the database.
+    virtual bool shouldBeEmptyOnDetach() const { return true; }
+
     /// Ask all tables to complete the background threads they are using and delete all table objects.
     virtual void shutdown() = 0;
 

src/Dictionaries/getDictionaryConfigurationFromAST.h

@@ -11,5 +11,4 @@ using DictionaryConfigurationPtr = Poco::AutoPtr<Poco::Util::AbstractConfigurati
 /// This function is necessary because all loadable objects configuration are Poco::AbstractConfiguration
 /// Can throw exception if query is ill-formed
 DictionaryConfigurationPtr getDictionaryConfigurationFromAST(const ASTCreateQuery & query);
-
 }

src/Interpreters/ExternalDictionariesLoader.cpp

@@ -1,5 +1,6 @@
 #include <Interpreters/ExternalDictionariesLoader.h>
 #include <Dictionaries/DictionaryFactory.h>
+#include <Dictionaries/DictionaryStructure.h>
 
 #if !defined(ARCADIA_BUILD)
 #    include "config_core.h"
@@ -33,6 +34,19 @@ ExternalLoader::LoadablePtr ExternalDictionariesLoader::create(
     return DictionaryFactory::instance().create(name, config, key_in_config, context, dictionary_from_database);
 }
 
+
+DictionaryStructure
+ExternalDictionariesLoader::getDictionaryStructure(const Poco::Util::AbstractConfiguration & config, const std::string & key_in_config)
+{
+    return {config, key_in_config + ".structure"};
+}
+
+DictionaryStructure ExternalDictionariesLoader::getDictionaryStructure(const ObjectConfig & config)
+{
+    return getDictionaryStructure(*config.config, config.key_in_config);
+}
+
+
 void ExternalDictionariesLoader::resetAll()
 {
 #if USE_MYSQL

src/Interpreters/ExternalDictionariesLoader.h

@@ -23,14 +23,14 @@ public:
         return std::static_pointer_cast<const IDictionaryBase>(load(name));
     }
 
-    DictPtr tryGetDictionary(const std::string & name, bool load) const
+    DictPtr tryGetDictionary(const std::string & name) const
     {
-        if (load)
+        return std::static_pointer_cast<const IDictionaryBase>(tryLoad(name));
-            return std::static_pointer_cast<const IDictionaryBase>(tryLoad(name));
-        else
-            return std::static_pointer_cast<const IDictionaryBase>(getCurrentLoadResult(name).object);
     }
 
+    static DictionaryStructure getDictionaryStructure(const Poco::Util::AbstractConfiguration & config, const std::string & key_in_config = "dictionary");
+    static DictionaryStructure getDictionaryStructure(const ObjectConfig & config);
+
     static void resetAll();
 
 protected:

src/Interpreters/ExternalLoader.cpp

@@ -94,15 +94,6 @@ namespace
     };
 }
 
-struct ExternalLoader::ObjectConfig
-{
-    Poco::AutoPtr<Poco::Util::AbstractConfiguration> config;
-    String key_in_config;
-    String repository_name;
-    bool from_temp_repository = false;
-    String path;
-};
-
 
 /** Reads configurations from configuration repository and parses it.
   */
@@ -141,7 +132,7 @@ public:
         settings = settings_;
     }
 
-    using ObjectConfigsPtr = std::shared_ptr<const std::unordered_map<String /* object's name */, ObjectConfig>>;
+    using ObjectConfigsPtr = std::shared_ptr<const std::unordered_map<String /* object's name */, std::shared_ptr<const ObjectConfig>>>;
 
     /// Reads all repositories.
     ObjectConfigsPtr read()
@@ -176,8 +167,9 @@ private:
     struct FileInfo
     {
         Poco::Timestamp last_update_time = 0;
-        std::vector<std::pair<String, ObjectConfig>> objects; // Parsed contents of the file.
         bool in_use = true; // Whether the `FileInfo` should be destroyed because the correspondent file is deleted.
+        Poco::AutoPtr<Poco::Util::AbstractConfiguration> file_contents; // Parsed contents of the file.
+        std::unordered_map<String /* object name */, String /* key in file_contents */> objects;
     };
 
     struct RepositoryInfo
@@ -280,14 +272,15 @@ private:
             }
 
             LOG_TRACE(log, "Loading config file '" << path << "'.");
-            auto file_contents = repository.load(path);
+            file_info.file_contents = repository.load(path);
+            auto & file_contents = *file_info.file_contents;
 
             /// get all objects' definitions
             Poco::Util::AbstractConfiguration::Keys keys;
-            file_contents->keys(keys);
+            file_contents.keys(keys);
 
             /// for each object defined in repositories
-            std::vector<std::pair<String, ObjectConfig>> object_configs_from_file;
+            std::unordered_map<String, String> objects;
             for (const auto & key : keys)
             {
                 if (!startsWith(key, settings.external_config))
@@ -297,7 +290,7 @@ private:
                     continue;
                 }
 
-                String object_name = file_contents->getString(key + "." + settings.external_name);
+                String object_name = file_contents.getString(key + "." + settings.external_name);
                 if (object_name.empty())
                 {
                     LOG_WARNING(log, path << ": node '" << key << "' defines " << type_name << " with an empty name. It's not allowed");
@@ -306,14 +299,14 @@ private:
 
                 String database;
                 if (!settings.external_database.empty())
-                    database = file_contents->getString(key + "." + settings.external_database, "");
+                    database = file_contents.getString(key + "." + settings.external_database, "");
                 if (!database.empty())
                     object_name = database + "." + object_name;
 
-                object_configs_from_file.emplace_back(object_name, ObjectConfig{file_contents, key, {}, {}, {}});
+                objects.emplace(object_name, key);
             }
 
-            file_info.objects = std::move(object_configs_from_file);
+            file_info.objects = std::move(objects);
             file_info.last_update_time = update_time_from_repository;
             file_info.in_use = true;
             return true;
@@ -333,33 +326,36 @@ private:
         need_collect_object_configs = false;
 
         // Generate new result.
-        auto new_configs = std::make_shared<std::unordered_map<String /* object's name */, ObjectConfig>>();
+        auto new_configs = std::make_shared<std::unordered_map<String /* object's name */, std::shared_ptr<const ObjectConfig>>>();
 
         for (const auto & [repository, repository_info] : repositories)
         {
             for (const auto & [path, file_info] : repository_info.files)
             {
-                for (const auto & [object_name, object_config] : file_info.objects)
+                for (const auto & [object_name, key_in_config] : file_info.objects)
                 {
                     auto already_added_it = new_configs->find(object_name);
                     if (already_added_it == new_configs->end())
                     {
-                        auto & new_config = new_configs->emplace(object_name, object_config).first->second;
+                        auto new_config = std::make_shared<ObjectConfig>();
-                        new_config.from_temp_repository = repository->isTemporary();
+                        new_config->config = file_info.file_contents;
-                        new_config.repository_name = repository->getName();
+                        new_config->key_in_config = key_in_config;
-                        new_config.path = path;
+                        new_config->repository_name = repository->getName();
+                        new_config->from_temp_repository = repository->isTemporary();
+                        new_config->path = path;
+                        new_configs->emplace(object_name, std::move(new_config));
                     }
                     else
                     {
                         const auto & already_added = already_added_it->second;
-                        if (!already_added.from_temp_repository && !repository->isTemporary())
+                        if (!already_added->from_temp_repository && !repository->isTemporary())
                         {
                             LOG_WARNING(
                                 log,
                                 type_name << " '" << object_name << "' is found "
-                                          << (((path == already_added.path) && (repository->getName() == already_added.repository_name))
+                                          << (((path == already_added->path) && (repository->getName() == already_added->repository_name))
                                                   ? ("twice in the same file '" + path + "'")
-                                                  : ("both in file '" + already_added.path + "' and '" + path + "'")));
+                                                  : ("both in file '" + already_added->path + "' and '" + path + "'")));
                         }
                     }
                 }
@@ -440,13 +436,10 @@ public:
             else
             {
                 const auto & new_config = new_config_it->second;
-                bool config_is_same = isSameConfiguration(*info.object_config.config, info.object_config.key_in_config, *new_config.config, new_config.key_in_config);
+                bool config_is_same = isSameConfiguration(*info.config->config, info.config->key_in_config, *new_config->config, new_config->key_in_config);
-                info.object_config = new_config;
+                info.config = new_config;
                 if (!config_is_same)
                 {
-                    /// Configuration has been changed.
-                    info.object_config = new_config;
-
                     if (info.triedToLoad())
                     {
                         /// The object has been tried to load before, so it is currently in use or was in use
@@ -531,7 +524,7 @@ public:
 
     /// Returns the load result of the object.
     template <typename ReturnType>
-    ReturnType getCurrentLoadResult(const String & name) const
+    ReturnType getLoadResult(const String & name) const
     {
         std::lock_guard lock{mutex};
         const Info * info = getInfo(name);
@@ -543,13 +536,13 @@ public:
     /// Returns all the load results as a map.
     /// The function doesn't load anything, it just returns the current load results as is.
     template <typename ReturnType>
-    ReturnType getCurrentLoadResults(const FilterByNameFunction & filter) const
+    ReturnType getLoadResults(const FilterByNameFunction & filter) const
     {
         std::lock_guard lock{mutex};
         return collectLoadResults<ReturnType>(filter);
     }
 
-    size_t getNumberOfCurrentlyLoadedObjects() const
+    size_t getNumberOfLoadedObjects() const
     {
         std::lock_guard lock{mutex};
         size_t count = 0;
@@ -562,7 +555,7 @@ public:
         return count;
     }
 
-    bool hasCurrentlyLoadedObjects() const
+    bool hasLoadedObjects() const
     {
         std::lock_guard lock{mutex};
         for (auto & name_info : infos)
@@ -581,6 +574,12 @@ public:
         return names;
     }
 
+    size_t getNumberOfObjects() const
+    {
+        std::lock_guard lock{mutex};
+        return infos.size();
+    }
+
     /// Tries to load a specified object during the timeout.
     template <typename ReturnType>
     ReturnType tryLoad(const String & name, Duration timeout)
@@ -698,7 +697,7 @@ public:
 private:
     struct Info
     {
-        Info(const String & name_, const ObjectConfig & object_config_) : name(name_), object_config(object_config_) {}
+        Info(const String & name_, const std::shared_ptr<const ObjectConfig> & config_) : name(name_), config(config_) {}
 
         bool loaded() const { return object != nullptr; }
         bool failed() const { return !object && exception; }
@@ -737,8 +736,7 @@ private:
                 result.loading_start_time = loading_start_time;
                 result.last_successful_update_time = last_successful_update_time;
                 result.loading_duration = loadingDuration();
-                result.origin = object_config.path;
+                result.config = config;
-                result.repository_name = object_config.repository_name;
                 return result;
             }
             else
@@ -750,7 +748,7 @@ private:
 
         String name;
         LoadablePtr object;
-        ObjectConfig object_config;
+        std::shared_ptr<const ObjectConfig> config;
         TimePoint loading_start_time;
         TimePoint loading_end_time;
         TimePoint last_successful_update_time;
@@ -784,7 +782,7 @@ private:
         results.reserve(infos.size());
         for (const auto & [name, info] : infos)
         {
-            if (filter(name))
+            if (!filter || filter(name))
             {
                 auto result = info.template getLoadResult<typename ReturnType::value_type>();
                 if constexpr (std::is_same_v<typename ReturnType::value_type, LoadablePtr>)
@@ -838,7 +836,7 @@ private:
             bool all_ready = true;
             for (auto & [name, info] : infos)
             {
-                if (!filter(name))
+                if (filter && !filter(name))
                     continue;
 
                 if (info.state_id >= min_id)
@@ -955,7 +953,7 @@ private:
                 previous_version_as_base_for_loading = nullptr; /// Need complete reloading, cannot use the previous version.
 
             /// Loading.
-            auto [new_object, new_exception] = loadSingleObject(name, info->object_config, previous_version_as_base_for_loading);
+            auto [new_object, new_exception] = loadSingleObject(name, *info->config, previous_version_as_base_for_loading);
             if (!new_object && !new_exception)
                 throw Exception("No object created and no exception raised for " + type_name, ErrorCodes::LOGICAL_ERROR);
 
@@ -1296,9 +1294,9 @@ void ExternalLoader::enablePeriodicUpdates(bool enable_)
     periodic_updater->enable(enable_);
 }
 
-bool ExternalLoader::hasCurrentlyLoadedObjects() const
+bool ExternalLoader::hasLoadedObjects() const
 {
-    return loading_dispatcher->hasCurrentlyLoadedObjects();
+    return loading_dispatcher->hasLoadedObjects();
 }
 
 ExternalLoader::Status ExternalLoader::getCurrentStatus(const String & name) const
@@ -1307,30 +1305,35 @@ ExternalLoader::Status ExternalLoader::getCurrentStatus(const String & name) con
 }
 
 template <typename ReturnType, typename>
-ReturnType ExternalLoader::getCurrentLoadResult(const String & name) const
+ReturnType ExternalLoader::getLoadResult(const String & name) const
 {
-    return loading_dispatcher->getCurrentLoadResult<ReturnType>(name);
+    return loading_dispatcher->getLoadResult<ReturnType>(name);
 }
 
 template <typename ReturnType, typename>
-ReturnType ExternalLoader::getCurrentLoadResults(const FilterByNameFunction & filter) const
+ReturnType ExternalLoader::getLoadResults(const FilterByNameFunction & filter) const
 {
-    return loading_dispatcher->getCurrentLoadResults<ReturnType>(filter);
+    return loading_dispatcher->getLoadResults<ReturnType>(filter);
 }
 
-ExternalLoader::Loadables ExternalLoader::getCurrentlyLoadedObjects() const
+ExternalLoader::Loadables ExternalLoader::getLoadedObjects() const
 {
-    return getCurrentLoadResults<Loadables>();
+    return getLoadResults<Loadables>();
 }
 
-ExternalLoader::Loadables ExternalLoader::getCurrentlyLoadedObjects(const FilterByNameFunction & filter) const
+ExternalLoader::Loadables ExternalLoader::getLoadedObjects(const FilterByNameFunction & filter) const
 {
-    return getCurrentLoadResults<Loadables>(filter);
+    return getLoadResults<Loadables>(filter);
 }
 
-size_t ExternalLoader::getNumberOfCurrentlyLoadedObjects() const
+size_t ExternalLoader::getNumberOfLoadedObjects() const
 {
-    return loading_dispatcher->getNumberOfCurrentlyLoadedObjects();
+    return loading_dispatcher->getNumberOfLoadedObjects();
+}
+
+size_t ExternalLoader::getNumberOfObjects() const
+{
+    return loading_dispatcher->getNumberOfObjects();
 }
 
 template <typename ReturnType, typename>
@@ -1456,10 +1459,10 @@ ExternalLoader::LoadablePtr ExternalLoader::createObject(
     return create(name, *config.config, config.key_in_config, config.repository_name);
 }
 
-template ExternalLoader::LoadablePtr ExternalLoader::getCurrentLoadResult<ExternalLoader::LoadablePtr>(const String &) const;
+template ExternalLoader::LoadablePtr ExternalLoader::getLoadResult<ExternalLoader::LoadablePtr>(const String &) const;
-template ExternalLoader::LoadResult ExternalLoader::getCurrentLoadResult<ExternalLoader::LoadResult>(const String &) const;
+template ExternalLoader::LoadResult ExternalLoader::getLoadResult<ExternalLoader::LoadResult>(const String &) const;
-template ExternalLoader::Loadables ExternalLoader::getCurrentLoadResults<ExternalLoader::Loadables>(const FilterByNameFunction &) const;
+template ExternalLoader::Loadables ExternalLoader::getLoadResults<ExternalLoader::Loadables>(const FilterByNameFunction &) const;
-template ExternalLoader::LoadResults ExternalLoader::getCurrentLoadResults<ExternalLoader::LoadResults>(const FilterByNameFunction &) const;
+template ExternalLoader::LoadResults ExternalLoader::getLoadResults<ExternalLoader::LoadResults>(const FilterByNameFunction &) const;
 
 template ExternalLoader::LoadablePtr ExternalLoader::tryLoad<ExternalLoader::LoadablePtr>(const String &, Duration) const;
 template ExternalLoader::LoadResult ExternalLoader::tryLoad<ExternalLoader::LoadResult>(const String &, Duration) const;

src/Interpreters/ExternalLoader.h

@@ -53,17 +53,25 @@ public:
     using Duration = std::chrono::milliseconds;
     using TimePoint = std::chrono::system_clock::time_point;
 
+    struct ObjectConfig
+    {
+        Poco::AutoPtr<Poco::Util::AbstractConfiguration> config;
+        String key_in_config;
+        String repository_name;
+        bool from_temp_repository = false;
+        String path;
+    };
+
     struct LoadResult
     {
         Status status = Status::NOT_EXIST;
         String name;
         LoadablePtr object;
-        String origin;
         TimePoint loading_start_time;
         TimePoint last_successful_update_time;
         Duration loading_duration;
         std::exception_ptr exception;
-        std::string repository_name;
+        std::shared_ptr<const ObjectConfig> config;
     };
 
     using LoadResults = std::vector<LoadResult>;
@@ -99,26 +107,32 @@ public:
     /// Returns the result of loading the object.
     /// The function doesn't load anything, it just returns the current load result as is.
     template <typename ReturnType = LoadResult, typename = std::enable_if_t<is_scalar_load_result_type<ReturnType>, void>>
-    ReturnType getCurrentLoadResult(const String & name) const;
+    ReturnType getLoadResult(const String & name) const;
 
     using FilterByNameFunction = std::function<bool(const String &)>;
 
     /// Returns all the load results as a map.
     /// The function doesn't load anything, it just returns the current load results as is.
     template <typename ReturnType = LoadResults, typename = std::enable_if_t<is_vector_load_result_type<ReturnType>, void>>
-    ReturnType getCurrentLoadResults() const { return getCurrentLoadResults<ReturnType>(alwaysTrue); }
+    ReturnType getLoadResults() const { return getLoadResults<ReturnType>(FilterByNameFunction{}); }
 
     template <typename ReturnType = LoadResults, typename = std::enable_if_t<is_vector_load_result_type<ReturnType>, void>>
-    ReturnType getCurrentLoadResults(const FilterByNameFunction & filter) const;
+    ReturnType getLoadResults(const FilterByNameFunction & filter) const;
 
     /// Returns all loaded objects as a map.
     /// The function doesn't load anything, it just returns the current load results as is.
-    Loadables getCurrentlyLoadedObjects() const;
+    Loadables getLoadedObjects() const;
-    Loadables getCurrentlyLoadedObjects(const FilterByNameFunction & filter) const;
+    Loadables getLoadedObjects(const FilterByNameFunction & filter) const;
 
     /// Returns true if any object was loaded.
-    bool hasCurrentlyLoadedObjects() const;
+    bool hasLoadedObjects() const;
-    size_t getNumberOfCurrentlyLoadedObjects() const;
+    size_t getNumberOfLoadedObjects() const;
+
+    /// Returns true if there is no object.
+    bool hasObjects() const { return getNumberOfObjects() == 0; }
+
+    /// Returns number of objects.
+    size_t getNumberOfObjects() const;
 
     static constexpr Duration NO_WAIT = Duration::zero();
     static constexpr Duration WAIT = Duration::max();
@@ -139,7 +153,7 @@ public:
     /// The function does nothing for already loaded objects, it just returns them.
     /// The function doesn't throw an exception if it's failed to load something.
     template <typename ReturnType = Loadables, typename = std::enable_if_t<is_vector_load_result_type<ReturnType>, void>>
-    ReturnType tryLoadAll(Duration timeout = WAIT) const { return tryLoad<ReturnType>(alwaysTrue, timeout); }
+    ReturnType tryLoadAll(Duration timeout = WAIT) const { return tryLoad<ReturnType>(FilterByNameFunction{}, timeout); }
 
     /// Loads a specified object.
     /// The function does nothing if it's already loaded.
@@ -157,7 +171,7 @@ public:
     /// The function does nothing for already loaded objects, it just returns them.
     /// The function throws an exception if it's failed to load something.
     template <typename ReturnType = Loadables, typename = std::enable_if_t<is_vector_load_result_type<ReturnType>, void>>
-    ReturnType loadAll() const { return load<ReturnType>(alwaysTrue); }
+    ReturnType loadAll() const { return load<ReturnType>(FilterByNameFunction{}); }
 
     /// Loads or reloads a specified object.
     /// The function reloads the object if it's already loaded.
@@ -174,7 +188,7 @@ public:
     /// Load or reloads all objects. Not recommended to use.
     /// The function throws an exception if it's failed to load or reload something.
     template <typename ReturnType = Loadables, typename = std::enable_if_t<is_vector_load_result_type<ReturnType>, void>>
-    ReturnType loadOrReloadAll() const { return loadOrReload<ReturnType>(alwaysTrue); }
+    ReturnType loadOrReloadAll() const { return loadOrReload<ReturnType>(FilterByNameFunction{}); }
 
     /// Reloads objects by filter which were tried to load before (successfully or not).
     /// The function throws an exception if it's failed to load or reload something.
@@ -197,10 +211,8 @@ private:
     void checkLoaded(const LoadResult & result, bool check_no_errors) const;
     void checkLoaded(const LoadResults & results, bool check_no_errors) const;
 
-    static bool alwaysTrue(const String &) { return true; }
     Strings getAllTriedToLoadNames() const;
 
-    struct ObjectConfig;
     LoadablePtr createObject(const String & name, const ObjectConfig & config, const LoadablePtr & previous_version) const;
 
     class LoadablesConfigReader;

src/Interpreters/ExternalLoaderDatabaseConfigRepository.cpp

@@ -1,30 +1,30 @@
 #include <Interpreters/ExternalLoaderDatabaseConfigRepository.h>
-#include <Interpreters/ExternalDictionariesLoader.h>
-#include <Dictionaries/getDictionaryConfigurationFromAST.h>
 #include <Common/StringUtils/StringUtils.h>
 
+
 namespace DB
 {
-
 namespace ErrorCodes
 {
     extern const int UNKNOWN_DICTIONARY;
 }
 
+
 namespace
 {
-String trimDatabaseName(const std::string & loadable_definition_name, const IDatabase & database)
+    String trimDatabaseName(const std::string & loadable_definition_name, const IDatabase & database)
-{
+    {
-    const auto & dbname = database.getDatabaseName();
+        const auto & dbname = database.getDatabaseName();
-    if (!startsWith(loadable_definition_name, dbname))
+        if (!startsWith(loadable_definition_name, dbname))
-        throw Exception(
+            throw Exception(
-            "Loadable '" + loadable_definition_name + "' is not from database '" + database.getDatabaseName(), ErrorCodes::UNKNOWN_DICTIONARY);
+                "Loadable '" + loadable_definition_name + "' is not from database '" + database.getDatabaseName(), ErrorCodes::UNKNOWN_DICTIONARY);
-    ///    dbname.loadable_name
+        ///    dbname.loadable_name
-    ///--> remove <---
+        ///--> remove <---
-    return loadable_definition_name.substr(dbname.length() + 1);
+        return loadable_definition_name.substr(dbname.length() + 1);
-}
+    }
 }
 
+
 ExternalLoaderDatabaseConfigRepository::ExternalLoaderDatabaseConfigRepository(IDatabase & database_, const Context & context_)
     : name(database_.getDatabaseName())
     , database(database_)
@@ -34,8 +34,7 @@ ExternalLoaderDatabaseConfigRepository::ExternalLoaderDatabaseConfigRepository(I
 
 LoadablesConfigurationPtr ExternalLoaderDatabaseConfigRepository::load(const std::string & loadable_definition_name)
 {
-    String dictname = trimDatabaseName(loadable_definition_name, database);
+    return database.getDictionaryConfiguration(trimDatabaseName(loadable_definition_name, database));
-    return getDictionaryConfigurationFromAST(database.getCreateDictionaryQuery(context, dictname)->as<const ASTCreateQuery &>());
 }
 
 bool ExternalLoaderDatabaseConfigRepository::exists(const std::string & loadable_definition_name)

src/Interpreters/InterpreterCreateQuery.cpp

@@ -45,6 +45,8 @@
 #include <Databases/DatabaseFactory.h>
 #include <Databases/IDatabase.h>
 
+#include <Dictionaries/getDictionaryConfigurationFromAST.h>
+
 #include <Compression/CompressionFactory.h>
 
 #include <Interpreters/InterpreterDropQuery.h>
@@ -703,7 +705,11 @@ BlockIO InterpreterCreateQuery::createDictionary(ASTCreateQuery & create)
     }
 
     if (create.attach)
-        database->attachDictionary(dictionary_name, context);
+    {
+        auto config = getDictionaryConfigurationFromAST(create);
+        auto modification_time = database->getObjectMetadataModificationTime(dictionary_name);
+        database->attachDictionary(dictionary_name, DictionaryAttachInfo{query_ptr, config, modification_time});
+    }
     else
         database->createDictionary(context, dictionary_name, query_ptr);
 

src/Interpreters/InterpreterDropQuery.cpp

@@ -188,7 +188,7 @@ BlockIO InterpreterDropQuery::executeToDictionary(
     {
         /// Drop dictionary from memory, don't touch data and metadata
         context.checkAccess(AccessType::DROP_DICTIONARY, database_name, dictionary_name);
-        database->detachDictionary(dictionary_name, context);
+        database->detachDictionary(dictionary_name);
     }
     else if (kind == ASTDropQuery::Kind::Truncate)
     {
@@ -254,21 +254,26 @@ BlockIO InterpreterDropQuery::executeToDatabase(const String & database_name, AS
             bool drop = kind == ASTDropQuery::Kind::Drop;
             context.checkAccess(AccessType::DROP_DATABASE, database_name);
 
-            /// DETACH or DROP all tables and dictionaries inside database
+            if (database->shouldBeEmptyOnDetach())
-            for (auto iterator = database->getTablesIterator(context); iterator->isValid(); iterator->next())
             {
-                String current_table_name = iterator->name();
+                /// DETACH or DROP all tables and dictionaries inside database.
-                executeToTable(database_name, current_table_name, kind, false, false, false);
+                /// First we should DETACH or DROP dictionaries because StorageDictionary
-            }
+                /// must be detached only by detaching corresponding dictionary.
+                for (auto iterator = database->getDictionariesIterator(context); iterator->isValid(); iterator->next())
+                {
+                    String current_dictionary = iterator->name();
+                    executeToDictionary(database_name, current_dictionary, kind, false, false, false);
+                }
 
-            for (auto iterator = database->getDictionariesIterator(context); iterator->isValid(); iterator->next())
+                for (auto iterator = database->getTablesIterator(context); iterator->isValid(); iterator->next())
-            {
+                {
-                String current_dictionary = iterator->name();
+                    String current_table_name = iterator->name();
-                executeToDictionary(database_name, current_dictionary, kind, false, false, false);
+                    executeToTable(database_name, current_table_name, kind, false, false, false);
+                }
             }
 
             /// DETACH or DROP database itself
-            DatabaseCatalog::instance().detachDatabase(database_name, drop);
+            DatabaseCatalog::instance().detachDatabase(database_name, drop, database->shouldBeEmptyOnDetach());
         }
     }
 

src/Storages/StorageDictionary.cpp

@@ -1,73 +1,48 @@
-#include <sstream>
-#include <DataTypes/DataTypesNumber.h>
-#include <DataTypes/DataTypeDate.h>
-#include <Dictionaries/IDictionarySource.h>
-#include <Dictionaries/DictionaryStructure.h>
 #include <Storages/StorageDictionary.h>
 #include <Storages/StorageFactory.h>
+#include <DataTypes/DataTypesNumber.h>
+#include <Dictionaries/DictionaryStructure.h>
 #include <Interpreters/Context.h>
 #include <Interpreters/evaluateConstantExpression.h>
 #include <Interpreters/ExternalDictionariesLoader.h>
 #include <Parsers/ASTLiteral.h>
-#include <common/logger_useful.h>
-#include <Common/typeid_cast.h>
 #include <Common/quoteString.h>
 #include <Processors/Sources/SourceFromInputStream.h>
 #include <Processors/Pipe.h>
+#include <sstream>
 
 
 namespace DB
 {
-
 namespace ErrorCodes
 {
     extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH;
     extern const int THERE_IS_NO_COLUMN;
-    extern const int UNKNOWN_TABLE;
+    extern const int CANNOT_DETACH_DICTIONARY_AS_TABLE;
 }
 
-
+namespace
-StorageDictionary::StorageDictionary(
-    const StorageID & table_id_,
-    const ColumnsDescription & columns_,
-    const Context & context,
-    bool attach,
-    const String & dictionary_name_)
-    : IStorage(table_id_)
-    , dictionary_name(dictionary_name_)
-    , logger(&Poco::Logger::get("StorageDictionary"))
 {
-    setColumns(columns_);
+    void checkNamesAndTypesCompatibleWithDictionary(const String & dictionary_name, const ColumnsDescription & columns, const DictionaryStructure & dictionary_structure)
-
-    if (!attach)
     {
-        const auto & dictionary = context.getExternalDictionariesLoader().getDictionary(dictionary_name);
+        auto dictionary_names_and_types = StorageDictionary::getNamesAndTypes(dictionary_structure);
-        const DictionaryStructure & dictionary_structure = dictionary->getStructure();
+        std::set<NameAndTypePair> names_and_types_set(dictionary_names_and_types.begin(), dictionary_names_and_types.end());
-        checkNamesAndTypesCompatibleWithDictionary(dictionary_structure);
+
+        for (const auto & column : columns.getOrdinary())
+        {
+            if (names_and_types_set.find(column) == names_and_types_set.end())
+            {
+                std::string message = "Not found column ";
+                message += column.name + " " + column.type->getName();
+                message += " in dictionary " + backQuote(dictionary_name) + ". ";
+                message += "There are only columns ";
+                message += StorageDictionary::generateNamesAndTypesDescription(dictionary_names_and_types);
+                throw Exception(message, ErrorCodes::THERE_IS_NO_COLUMN);
+            }
+        }
     }
 }
 
-void StorageDictionary::checkTableCanBeDropped() const
-{
-    throw Exception("Cannot detach dictionary " + backQuoteIfNeed(dictionary_name) + " as table, use DETACH DICTIONARY query.", ErrorCodes::UNKNOWN_TABLE);
-}
-
-Pipes StorageDictionary::read(
-    const Names & column_names,
-    const SelectQueryInfo & /*query_info*/,
-    const Context & context,
-    QueryProcessingStage::Enum /*processed_stage*/,
-    const size_t max_block_size,
-    const unsigned /*threads*/)
-{
-    auto dictionary = context.getExternalDictionariesLoader().getDictionary(dictionary_name);
-    auto stream = dictionary->getBlockInputStream(column_names, max_block_size);
-    auto source = std::make_shared<SourceFromInputStream>(stream);
-    /// TODO: update dictionary interface for processors.
-    Pipes pipes;
-    pipes.emplace_back(std::move(source));
-    return pipes;
-}
 
 NamesAndTypesList StorageDictionary::getNamesAndTypes(const DictionaryStructure & dictionary_structure)
 {
@@ -103,25 +78,55 @@ NamesAndTypesList StorageDictionary::getNamesAndTypes(const DictionaryStructure
     return dictionary_names_and_types;
 }
 
-void StorageDictionary::checkNamesAndTypesCompatibleWithDictionary(const DictionaryStructure & dictionary_structure) const
-{
-    auto dictionary_names_and_types = getNamesAndTypes(dictionary_structure);
-    std::set<NameAndTypePair> names_and_types_set(dictionary_names_and_types.begin(), dictionary_names_and_types.end());
 
-    for (const auto & column : getColumns().getOrdinary())
+String StorageDictionary::generateNamesAndTypesDescription(const NamesAndTypesList & list)
+{
+    std::stringstream ss;
+    bool first = true;
+    for (const auto & name_and_type : list)
     {
-        if (names_and_types_set.find(column) == names_and_types_set.end())
+        if (!std::exchange(first, false))
-        {
+            ss << ", ";
-            std::string message = "Not found column ";
+        ss << name_and_type.name << ' ' << name_and_type.type->getName();
-            message += column.name + " " + column.type->getName();
-            message += " in dictionary " + dictionary_name + ". ";
-            message += "There are only columns ";
-            message += generateNamesAndTypesDescription(dictionary_names_and_types.begin(), dictionary_names_and_types.end());
-            throw Exception(message, ErrorCodes::THERE_IS_NO_COLUMN);
-        }
     }
+    return ss.str();
 }
 
+
+StorageDictionary::StorageDictionary(
+    const StorageID & table_id_,
+    const String & dictionary_name_,
+    const DictionaryStructure & dictionary_structure_)
+    : IStorage(table_id_)
+    , dictionary_name(dictionary_name_)
+{
+    setColumns(ColumnsDescription{getNamesAndTypes(dictionary_structure_)});
+}
+
+
+void StorageDictionary::checkTableCanBeDropped() const
+{
+    throw Exception("Cannot detach dictionary " + backQuote(dictionary_name) + " as table, use DETACH DICTIONARY query.", ErrorCodes::CANNOT_DETACH_DICTIONARY_AS_TABLE);
+}
+
+Pipes StorageDictionary::read(
+    const Names & column_names,
+    const SelectQueryInfo & /*query_info*/,
+    const Context & context,
+    QueryProcessingStage::Enum /*processed_stage*/,
+    const size_t max_block_size,
+    const unsigned /*threads*/)
+{
+    auto dictionary = context.getExternalDictionariesLoader().getDictionary(dictionary_name);
+    auto stream = dictionary->getBlockInputStream(column_names, max_block_size);
+    auto source = std::make_shared<SourceFromInputStream>(stream);
+    /// TODO: update dictionary interface for processors.
+    Pipes pipes;
+    pipes.emplace_back(std::move(source));
+    return pipes;
+}
+
+
 void registerStorageDictionary(StorageFactory & factory)
 {
     factory.registerStorage("Dictionary", [](const StorageFactory::Arguments & args)
@@ -133,8 +138,11 @@ void registerStorageDictionary(StorageFactory & factory)
         args.engine_args[0] = evaluateConstantExpressionOrIdentifierAsLiteral(args.engine_args[0], args.local_context);
         String dictionary_name = args.engine_args[0]->as<ASTLiteral &>().value.safeGet<String>();
 
-        return StorageDictionary::create(
+        const auto & dictionary = args.context.getExternalDictionariesLoader().getDictionary(dictionary_name);
-            args.table_id, args.columns, args.context, args.attach, dictionary_name);
+        const DictionaryStructure & dictionary_structure = dictionary->getStructure();
+        checkNamesAndTypesCompatibleWithDictionary(dictionary_name, args.columns, dictionary_structure);
+
+        return StorageDictionary::create(args.table_id, dictionary_name, dictionary_structure);
     });
 }
 

src/Storages/StorageDictionary.h

@@ -1,23 +1,12 @@
 #pragma once
 
 #include <Storages/IStorage.h>
-#include <Core/Defines.h>
-#include <Common/MultiVersion.h>
 #include <ext/shared_ptr_helper.h>
-#include <IO/WriteBufferFromString.h>
-#include <IO/Operators.h>
 
 
-namespace Poco
-{
-class Logger;
-}
-
 namespace DB
 {
 struct DictionaryStructure;
-struct IDictionaryBase;
-class ExternalDictionaries;
 
 class StorageDictionary final : public ext::shared_ptr_helper<StorageDictionary>, public IStorage
 {
@@ -35,42 +24,16 @@ public:
         unsigned threads) override;
 
     static NamesAndTypesList getNamesAndTypes(const DictionaryStructure & dictionary_structure);
-
+    static String generateNamesAndTypesDescription(const NamesAndTypesList & list);
-    template <typename ForwardIterator>
-    static std::string generateNamesAndTypesDescription(ForwardIterator begin, ForwardIterator end)
-    {
-        std::string description;
-        {
-            WriteBufferFromString buffer(description);
-            bool first = true;
-            for (; begin != end; ++begin)
-            {
-                if (!first)
-                    buffer << ", ";
-                first = false;
-
-                buffer << begin->name << ' ' << begin->type->getName();
-            }
-        }
-
-        return description;
-    }
 
 private:
-    using Ptr = MultiVersion<IDictionaryBase>::Version;
-
     String dictionary_name;
-    Poco::Logger * logger;
-
-    void checkNamesAndTypesCompatibleWithDictionary(const DictionaryStructure & dictionary_structure) const;
 
 protected:
     StorageDictionary(
         const StorageID & table_id_,
-        const ColumnsDescription & columns_,
+        const String & dictionary_name_,
-        const Context & context,
+        const DictionaryStructure & dictionary_structure);
-        bool attach,
-        const String & dictionary_name_);
 };
 
 }

src/Storages/System/StorageSystemColumns.cpp

@@ -303,7 +303,7 @@ Pipes StorageSystemColumns::read(
             const DatabasePtr database = databases.at(database_name);
             offsets[i] = i ? offsets[i - 1] : 0;
 
-            for (auto iterator = database->getTablesWithDictionaryTablesIterator(context); iterator->isValid(); iterator->next())
+            for (auto iterator = database->getTablesIterator(context); iterator->isValid(); iterator->next())
             {
                 const String & table_name = iterator->name();
                 storages.emplace(std::piecewise_construct,

src/Storages/System/StorageSystemDictionaries.cpp

@@ -53,7 +53,7 @@ void StorageSystemDictionaries::fillData(MutableColumns & res_columns, const Con
     const bool check_access_for_dictionaries = !access->isGranted(AccessType::SHOW_DICTIONARIES);
 
     const auto & external_dictionaries = context.getExternalDictionariesLoader();
-    for (const auto & load_result : external_dictionaries.getCurrentLoadResults())
+    for (const auto & load_result : external_dictionaries.getLoadResults())
     {
         const auto dict_ptr = std::dynamic_pointer_cast<const IDictionaryBase>(load_result.object);
 
@@ -66,9 +66,10 @@ void StorageSystemDictionaries::fillData(MutableColumns & res_columns, const Con
         else
         {
             short_name = load_result.name;
-            if (!load_result.repository_name.empty() && startsWith(short_name, load_result.repository_name + "."))
+            String repository_name = load_result.config ? load_result.config->repository_name : "";
+            if (!repository_name.empty() && startsWith(short_name, repository_name + "."))
             {
-                database = load_result.repository_name;
+                database = repository_name;
                 short_name = short_name.substr(database.length() + 1);
             }
         }
@@ -81,7 +82,7 @@ void StorageSystemDictionaries::fillData(MutableColumns & res_columns, const Con
         res_columns[i++]->insert(database);
         res_columns[i++]->insert(short_name);
         res_columns[i++]->insert(static_cast<Int8>(load_result.status));
-        res_columns[i++]->insert(load_result.origin);
+        res_columns[i++]->insert(load_result.config ? load_result.config->path : "");
 
         std::exception_ptr last_exception = load_result.exception;
 

src/Storages/System/StorageSystemModels.cpp

@@ -28,13 +28,13 @@ NamesAndTypesList StorageSystemModels::getNamesAndTypes()
 void StorageSystemModels::fillData(MutableColumns & res_columns, const Context & context, const SelectQueryInfo &) const
 {
     const auto & external_models_loader = context.getExternalModelsLoader();
-    auto load_results = external_models_loader.getCurrentLoadResults();
+    auto load_results = external_models_loader.getLoadResults();
 
     for (const auto & load_result : load_results)
     {
         res_columns[0]->insert(load_result.name);
         res_columns[1]->insert(static_cast<Int8>(load_result.status));
-        res_columns[2]->insert(load_result.origin);
+        res_columns[2]->insert(load_result.config ? load_result.config->path : "");
 
         if (load_result.object)
         {

src/Storages/System/StorageSystemTables.cpp

@@ -226,7 +226,7 @@ protected:
             const bool check_access_for_tables = check_access_for_databases && !access->isGranted(AccessType::SHOW_TABLES, database_name);
 
             if (!tables_it || !tables_it->isValid())
-                tables_it = database->getTablesWithDictionaryTablesIterator(context);
+                tables_it = database->getTablesIterator(context);
 
             const bool need_lock_structure = needLockStructure(database, getPort().getHeader());
 

tests/queries/0_stateless/01018_dictionaries_from_dictionaries.reference

@@ -9,6 +9,7 @@
 dict1
 dict2
 dict3
+dict4
 table_for_dict
 dict1
 dict2

tests/queries/0_stateless/01048_exists_query.sql

@@ -32,7 +32,7 @@ EXISTS TABLE db_01048.t_01048; -- Dictionaries are tables as well. But not all t
 EXISTS DICTIONARY db_01048.t_01048;
 
 -- But dictionary-tables cannot be dropped as usual tables.
-DROP TABLE db_01048.t_01048; -- { serverError 60 }
+DROP TABLE db_01048.t_01048; -- { serverError 520 }
 DROP DICTIONARY db_01048.t_01048;
 EXISTS db_01048.t_01048;
 EXISTS TABLE db_01048.t_01048;

tests/queries/0_stateless/01224_no_superfluous_dict_reload.reference

@@ -16,4 +16,9 @@ CREATE TABLE dict_db_01224_dictionary.`dict_db_01224.dict`
     `val` UInt64
 )
 ENGINE = Dictionary(`dict_db_01224.dict`)
-LOADED
+NOT_LOADED
+Dictionary	1	CREATE DICTIONARY dict_db_01224.dict (`key` UInt64 DEFAULT 0, `val` UInt64 DEFAULT 10) PRIMARY KEY key SOURCE(CLICKHOUSE(HOST \'localhost\' PORT 9000 USER \'default\' TABLE \'dict_data\' PASSWORD \'\' DB \'dict_db_01224\')) LIFETIME(MIN 0 MAX 0) LAYOUT(FLAT())
+NOT_LOADED
+key	UInt64
+val	UInt64
+NOT_LOADED

tests/queries/0_stateless/01224_no_superfluous_dict_reload.sql

@@ -1,6 +1,7 @@
 DROP DATABASE IF EXISTS dict_db_01224;
 DROP DATABASE IF EXISTS dict_db_01224_dictionary;
 CREATE DATABASE dict_db_01224;
+CREATE DATABASE dict_db_01224_dictionary Engine=Dictionary;
 
 CREATE TABLE dict_db_01224.dict_data (key UInt64, val UInt64) Engine=Memory();
 CREATE DICTIONARY dict_db_01224.dict
@@ -21,10 +22,15 @@ SELECT status FROM system.dictionaries WHERE database = 'dict_db_01224' AND name
 SHOW CREATE TABLE dict_db_01224.dict FORMAT TSVRaw;
 SELECT status FROM system.dictionaries WHERE database = 'dict_db_01224' AND name = 'dict';
 
-CREATE DATABASE dict_db_01224_dictionary Engine=Dictionary;
 SHOW CREATE TABLE dict_db_01224_dictionary.`dict_db_01224.dict` FORMAT TSVRaw;
 SELECT status FROM system.dictionaries WHERE database = 'dict_db_01224' AND name = 'dict';
 
+SELECT engine, metadata_path LIKE '%/metadata/dict\_db\_01224/dict.sql', create_table_query FROM system.tables WHERE database = 'dict_db_01224' AND name = 'dict';
+SELECT status FROM system.dictionaries WHERE database = 'dict_db_01224' AND name = 'dict';
+
+SELECT name, type FROM system.columns WHERE database = 'dict_db_01224' AND table = 'dict';
+SELECT status FROM system.dictionaries WHERE database = 'dict_db_01224' AND name = 'dict';
+
 DROP DICTIONARY dict_db_01224.dict;
 SELECT status FROM system.dictionaries WHERE database = 'dict_db_01224' AND name = 'dict';
 

tests/queries/0_stateless/01225_drop_dictionary_as_table.sql

@@ -13,8 +13,8 @@ LIFETIME(MIN 0 MAX 0)
 LAYOUT(FLAT());
 
 SYSTEM RELOAD DICTIONARY dict_db_01225.dict;
-DROP TABLE dict_db_01225.dict; -- { serverError 60; }
+
--- Regression:
+DROP TABLE dict_db_01225.dict; -- { serverError 520; }
---     Code: 1000. DB::Exception: Received from localhost:9000. DB::Exception: File not found: ./metadata/dict_db_01225/dict.sql.
 DROP DICTIONARY dict_db_01225.dict;
+
 DROP DATABASE dict_db_01225;

tests/queries/0_stateless/01225_show_create_table_from_dictionary.sql

@@ -15,7 +15,7 @@ LIFETIME(MIN 0 MAX 0)
 LAYOUT(FLAT());
 
 SHOW CREATE TABLE dict_db_01225_dictionary.`dict_db_01225.dict` FORMAT TSVRaw;
-SHOW CREATE TABLE dict_db_01225_dictionary.`dict_db_01225.no_such_dict`; -- { serverError 36; }
+SHOW CREATE TABLE dict_db_01225_dictionary.`dict_db_01225.no_such_dict`; -- { serverError 487; }
 
 DROP DATABASE dict_db_01225;
 DROP DATABASE dict_db_01225_dictionary;