Merge pull request #22697 from TCeason/feature/add_MaterializeMySQL_sync_bytes_judgment

Add MySQL read history data bytes judgment

src/Core/Settings.h

@@ -446,6 +446,8 @@ class IColumn;
     M(Bool, database_replicated_always_detach_permanently, false, "Execute DETACH TABLE as DETACH TABLE PERMANENTLY if database engine is Replicated", 0) \
     M(DistributedDDLOutputMode, distributed_ddl_output_mode, DistributedDDLOutputMode::THROW, "Format of distributed DDL query result", 0) \
     M(UInt64, distributed_ddl_entry_format_version, 1, "Version of DDL entry to write into ZooKeeper", 0) \
+    M(UInt64, external_storage_max_read_rows, 0, "Limit maximum number of rows when table with external engine should flush history data. Now supported only for MySQL table engine, database engine, dictionary and MaterializeMySQL. If equal to 0, this setting is disabled", 0) \
+    M(UInt64, external_storage_max_read_bytes, 0, "Limit maximum number of bytes when table with external engine should flush history data. Now supported only for MySQL table engine, database engine, dictionary and MaterializeMySQL. If equal to 0, this setting is disabled", 0)  \
     \
     /** Obsolete settings that do nothing but left for compatibility reasons. Remove each one after half a year of obsolescence. */ \
     \

src/Databases/MySQL/DatabaseConnectionMySQL.cpp

@@ -198,7 +198,7 @@ ASTPtr DatabaseConnectionMySQL::getCreateDatabaseQuery() const
 
 void DatabaseConnectionMySQL::fetchTablesIntoLocalCache(ContextPtr local_context) const
 {
-    const auto & tables_with_modification_time = fetchTablesWithModificationTime();
+    const auto & tables_with_modification_time = fetchTablesWithModificationTime(local_context);
 
     destroyLocalCacheExtraTables(tables_with_modification_time);
     fetchLatestTablesStructureIntoCache(tables_with_modification_time, local_context);
@@ -252,7 +252,7 @@ void DatabaseConnectionMySQL::fetchLatestTablesStructureIntoCache(
     }
 }
 
-std::map<String, UInt64> DatabaseConnectionMySQL::fetchTablesWithModificationTime() const
+std::map<String, UInt64> DatabaseConnectionMySQL::fetchTablesWithModificationTime(ContextPtr local_context) const
 {
     Block tables_status_sample_block
     {
@@ -268,7 +268,8 @@ std::map<String, UInt64> DatabaseConnectionMySQL::fetchTablesWithModificationTim
              " WHERE TABLE_SCHEMA = " << quote << database_name_in_mysql;
 
     std::map<String, UInt64> tables_with_modification_time;
-    MySQLBlockInputStream result(mysql_pool.get(), query.str(), tables_status_sample_block, DEFAULT_BLOCK_SIZE);
+    StreamSettings mysql_input_stream_settings(local_context->getSettingsRef());
+    MySQLBlockInputStream result(mysql_pool.get(), query.str(), tables_status_sample_block, mysql_input_stream_settings);
 
     while (Block block = result.read())
     {
@@ -292,7 +293,7 @@ DatabaseConnectionMySQL::fetchTablesColumnsList(const std::vector<String> & tabl
             mysql_pool,
             database_name_in_mysql,
             tables_name,
-            settings.external_table_functions_use_nulls,
+            settings,
             database_settings->mysql_datatypes_support_level);
 }
 

src/Databases/MySQL/DatabaseConnectionMySQL.h

@@ -108,7 +108,7 @@ private:
 
     void fetchTablesIntoLocalCache(ContextPtr context) const;
 
-    std::map<String, UInt64> fetchTablesWithModificationTime() const;
+    std::map<String, UInt64> fetchTablesWithModificationTime(ContextPtr local_context) const;
 
     std::map<String, NamesAndTypesList> fetchTablesColumnsList(const std::vector<String> & tables_name, ContextPtr context) const;
 

src/Databases/MySQL/FetchTablesColumnsList.cpp

@@ -44,7 +44,7 @@ std::map<String, NamesAndTypesList> fetchTablesColumnsList(
         mysqlxx::PoolWithFailover & pool,
         const String & database_name,
         const std::vector<String> & tables_name,
-        bool external_table_functions_use_nulls,
+        const Settings & settings,
         MultiEnum<MySQLDataTypesSupport> type_support)
 {
     std::map<String, NamesAndTypesList> tables_and_columns;
@@ -78,7 +78,8 @@ std::map<String, NamesAndTypesList> fetchTablesColumnsList(
              " WHERE TABLE_SCHEMA = " << quote << database_name
           << " AND TABLE_NAME IN " << toQueryStringWithQuote(tables_name) << " ORDER BY ORDINAL_POSITION";
 
-    MySQLBlockInputStream result(pool.get(), query.str(), tables_columns_sample_block, DEFAULT_BLOCK_SIZE);
+    StreamSettings mysql_input_stream_settings(settings);
+    MySQLBlockInputStream result(pool.get(), query.str(), tables_columns_sample_block, mysql_input_stream_settings);
     while (Block block = result.read())
     {
         const auto & table_name_col = *block.getByPosition(0).column;
@@ -99,7 +100,7 @@ std::map<String, NamesAndTypesList> fetchTablesColumnsList(
                     convertMySQLDataType(
                             type_support,
                             column_type_col[i].safeGet<String>(),
-                            external_table_functions_use_nulls && is_nullable_col[i].safeGet<UInt64>(),
+                            settings.external_table_functions_use_nulls && is_nullable_col[i].safeGet<UInt64>(),
                             is_unsigned_col[i].safeGet<UInt64>(),
                             char_max_length_col[i].safeGet<UInt64>(),
                             precision_col[i].safeGet<UInt64>(),

src/Databases/MySQL/FetchTablesColumnsList.h

@@ -12,6 +12,7 @@
 
 #include <map>
 #include <vector>
+#include <Core/Settings.h>
 
 namespace DB
 {
@@ -20,7 +21,7 @@ std::map<String, NamesAndTypesList> fetchTablesColumnsList(
         mysqlxx::PoolWithFailover & pool,
         const String & database_name,
         const std::vector<String> & tables_name,
-        bool external_table_functions_use_nulls,
+        const Settings & settings,
         MultiEnum<MySQLDataTypesSupport> type_support);
 
 }

src/Databases/MySQL/MaterializeMetadata.cpp

@@ -24,7 +24,8 @@ namespace ErrorCodes
 }
 
 static std::unordered_map<String, String> fetchTablesCreateQuery(
-    const mysqlxx::PoolWithFailover::Entry & connection, const String & database_name, const std::vector<String> & fetch_tables)
+    const mysqlxx::PoolWithFailover::Entry & connection, const String & database_name,
+    const std::vector<String> & fetch_tables, const Settings & global_settings)
 {
     std::unordered_map<String, String> tables_create_query;
     for (const auto & fetch_table_name : fetch_tables)
@@ -34,9 +35,10 @@ static std::unordered_map<String, String> fetchTablesCreateQuery(
             {std::make_shared<DataTypeString>(), "Create Table"},
         };
 
+        StreamSettings mysql_input_stream_settings(global_settings, false, true);
         MySQLBlockInputStream show_create_table(
             connection, "SHOW CREATE TABLE " + backQuoteIfNeed(database_name) + "." + backQuoteIfNeed(fetch_table_name),
-            show_create_table_header, DEFAULT_BLOCK_SIZE, false, true);
+            show_create_table_header, mysql_input_stream_settings);
 
         Block create_query_block = show_create_table.read();
         if (!create_query_block || create_query_block.rows() != 1)
@@ -49,13 +51,14 @@ static std::unordered_map<String, String> fetchTablesCreateQuery(
 }
 
 
-static std::vector<String> fetchTablesInDB(const mysqlxx::PoolWithFailover::Entry & connection, const std::string & database)
+static std::vector<String> fetchTablesInDB(const mysqlxx::PoolWithFailover::Entry & connection, const std::string & database, const Settings & global_settings)
 {
     Block header{{std::make_shared<DataTypeString>(), "table_name"}};
     String query = "SELECT TABLE_NAME AS table_name FROM INFORMATION_SCHEMA.TABLES  WHERE TABLE_TYPE != 'VIEW' AND TABLE_SCHEMA = " + quoteString(database);
 
     std::vector<String> tables_in_db;
-    MySQLBlockInputStream input(connection, query, header, DEFAULT_BLOCK_SIZE);
+    StreamSettings mysql_input_stream_settings(global_settings);
+    MySQLBlockInputStream input(connection, query, header, mysql_input_stream_settings);
 
     while (Block block = input.read())
     {
@@ -77,7 +80,8 @@ void MaterializeMetadata::fetchMasterStatus(mysqlxx::PoolWithFailover::Entry & c
         {std::make_shared<DataTypeString>(), "Executed_Gtid_Set"},
     };
 
-    MySQLBlockInputStream input(connection, "SHOW MASTER STATUS;", header, DEFAULT_BLOCK_SIZE, false, true);
+    StreamSettings mysql_input_stream_settings(settings, false, true);
+    MySQLBlockInputStream input(connection, "SHOW MASTER STATUS;", header, mysql_input_stream_settings);
     Block master_status = input.read();
 
     if (!master_status || master_status.rows() != 1)
@@ -99,7 +103,8 @@ void MaterializeMetadata::fetchMasterVariablesValue(const mysqlxx::PoolWithFailo
     };
 
     const String & fetch_query = "SHOW VARIABLES WHERE Variable_name = 'binlog_checksum'";
-    MySQLBlockInputStream variables_input(connection, fetch_query, variables_header, DEFAULT_BLOCK_SIZE, false, true);
+    StreamSettings mysql_input_stream_settings(settings, false, true);
+    MySQLBlockInputStream variables_input(connection, fetch_query, variables_header, mysql_input_stream_settings);
 
     while (Block variables_block = variables_input.read())
     {
@@ -114,7 +119,7 @@ void MaterializeMetadata::fetchMasterVariablesValue(const mysqlxx::PoolWithFailo
     }
 }
 
-static bool checkSyncUserPrivImpl(const mysqlxx::PoolWithFailover::Entry & connection, WriteBuffer & out)
+static bool checkSyncUserPrivImpl(const mysqlxx::PoolWithFailover::Entry & connection, const Settings & global_settings, WriteBuffer & out)
 {
     Block sync_user_privs_header
     {
@@ -122,7 +127,8 @@ static bool checkSyncUserPrivImpl(const mysqlxx::PoolWithFailover::Entry & conne
     };
 
     String grants_query, sub_privs;
-    MySQLBlockInputStream input(connection, "SHOW GRANTS FOR CURRENT_USER();", sync_user_privs_header, DEFAULT_BLOCK_SIZE);
+    StreamSettings mysql_input_stream_settings(global_settings);
+    MySQLBlockInputStream input(connection, "SHOW GRANTS FOR CURRENT_USER();", sync_user_privs_header, mysql_input_stream_settings);
     while (Block block = input.read())
     {
         for (size_t index = 0; index < block.rows(); ++index)
@@ -146,11 +152,11 @@ static bool checkSyncUserPrivImpl(const mysqlxx::PoolWithFailover::Entry & conne
     return false;
 }
 
-static void checkSyncUserPriv(const mysqlxx::PoolWithFailover::Entry & connection)
+static void checkSyncUserPriv(const mysqlxx::PoolWithFailover::Entry & connection, const Settings & global_settings)
 {
     WriteBufferFromOwnString out;
 
-    if (!checkSyncUserPrivImpl(connection, out))
+    if (!checkSyncUserPrivImpl(connection, global_settings, out))
         throw Exception("MySQL SYNC USER ACCESS ERR: mysql sync user needs "
                         "at least GLOBAL PRIVILEGES:'RELOAD, REPLICATION SLAVE, REPLICATION CLIENT' "
                         "and SELECT PRIVILEGE on MySQL Database."
@@ -167,7 +173,8 @@ bool MaterializeMetadata::checkBinlogFileExists(const mysqlxx::PoolWithFailover:
         {std::make_shared<DataTypeUInt64>(), "File_size"}
     };
 
-    MySQLBlockInputStream input(connection, "SHOW MASTER LOGS", logs_header, DEFAULT_BLOCK_SIZE, false, true);
+    StreamSettings mysql_input_stream_settings(settings, false, true);
+    MySQLBlockInputStream input(connection, "SHOW MASTER LOGS", logs_header, mysql_input_stream_settings);
 
     while (Block block = input.read())
     {
@@ -222,7 +229,7 @@ void MaterializeMetadata::transaction(const MySQLReplication::Position & positio
     commitMetadata(std::move(fun), persistent_tmp_path, persistent_path);
 }
 
-MaterializeMetadata::MaterializeMetadata(const String & path_) : persistent_path(path_)
+MaterializeMetadata::MaterializeMetadata(const String & path_, const Settings & settings_) : persistent_path(path_), settings(settings_)
 {
     if (Poco::File(persistent_path).exists())
     {
@@ -244,7 +251,7 @@ void MaterializeMetadata::startReplication(
     mysqlxx::PoolWithFailover::Entry & connection, const String & database,
     bool & opened_transaction, std::unordered_map<String, String> & need_dumping_tables)
 {
-    checkSyncUserPriv(connection);
+    checkSyncUserPriv(connection, settings);
 
     if (checkBinlogFileExists(connection))
       return;
@@ -263,7 +270,7 @@ void MaterializeMetadata::startReplication(
         connection->query("START TRANSACTION /*!40100 WITH CONSISTENT SNAPSHOT */;").execute();
 
         opened_transaction = true;
-        need_dumping_tables = fetchTablesCreateQuery(connection, database, fetchTablesInDB(connection, database));
+        need_dumping_tables = fetchTablesCreateQuery(connection, database, fetchTablesInDB(connection, database, settings), settings);
         connection->query("UNLOCK TABLES;").execute();
     }
     catch (...)

src/Databases/MySQL/MaterializeMetadata.h

@@ -10,6 +10,7 @@
 #include <Core/MySQL/MySQLReplication.h>
 #include <mysqlxx/Connection.h>
 #include <mysqlxx/PoolWithFailover.h>
+#include <Interpreters/Context.h>
 
 namespace DB
 {
@@ -25,6 +26,7 @@ namespace DB
 struct MaterializeMetadata
 {
     const String persistent_path;
+    const Settings settings;
 
     String binlog_file;
     UInt64 binlog_position;
@@ -50,7 +52,7 @@ struct MaterializeMetadata
         bool & opened_transaction,
         std::unordered_map<String, String> & need_dumping_tables);
 
-    MaterializeMetadata(const String & path_);
+    MaterializeMetadata(const String & path_, const Settings & settings_);
 };
 
 }

src/Databases/MySQL/MaterializeMySQLSyncThread.cpp

@@ -90,7 +90,7 @@ MaterializeMySQLSyncThread::~MaterializeMySQLSyncThread()
     }
 }
 
-static void checkMySQLVariables(const mysqlxx::Pool::Entry & connection)
+static void checkMySQLVariables(const mysqlxx::Pool::Entry & connection, const Settings & settings)
 {
     Block variables_header{
         {std::make_shared<DataTypeString>(), "Variable_name"},
@@ -104,19 +104,19 @@ static void checkMySQLVariables(const mysqlxx::Pool::Entry & connection)
          "OR (Variable_name = 'default_authentication_plugin' AND upper(Value) = 'MYSQL_NATIVE_PASSWORD') "
          "OR (Variable_name = 'log_bin_use_v1_row_events' AND upper(Value) = 'OFF');";
 
-    MySQLBlockInputStream variables_input(connection, check_query, variables_header, DEFAULT_BLOCK_SIZE, false, true);
+    StreamSettings mysql_input_stream_settings(settings, false, true);
+    MySQLBlockInputStream variables_input(connection, check_query, variables_header, mysql_input_stream_settings);
 
-    Block variables_block = variables_input.read();
+    std::unordered_map<String, String> variables_error_message{
-    if (!variables_block || variables_block.rows() != 5)
+        {"log_bin", "log_bin = 'ON'"},
+        {"binlog_format", "binlog_format='ROW'"},
+        {"binlog_row_image", "binlog_row_image='FULL'"},
+        {"default_authentication_plugin", "default_authentication_plugin='mysql_native_password'"},
+        {"log_bin_use_v1_row_events", "log_bin_use_v1_row_events='OFF'"}
+    };
+
+    while (Block variables_block = variables_input.read())
     {
-        std::unordered_map<String, String> variables_error_message{
-            {"log_bin", "log_bin = 'ON'"},
-            {"binlog_format", "binlog_format='ROW'"},
-            {"binlog_row_image", "binlog_row_image='FULL'"},
-            {"default_authentication_plugin", "default_authentication_plugin='mysql_native_password'"},
-            {"log_bin_use_v1_row_events", "log_bin_use_v1_row_events='OFF'"}
-        };
-
         ColumnPtr variable_name_column = variables_block.getByName("Variable_name").column;
 
         for (size_t index = 0; index < variables_block.rows(); ++index)
@@ -126,7 +126,10 @@ static void checkMySQLVariables(const mysqlxx::Pool::Entry & connection)
             if (error_message_it != variables_error_message.end())
                 variables_error_message.erase(error_message_it);
         }
+    }
 
+    if  (!variables_error_message.empty())
+    {
         bool first = true;
         WriteBufferFromOwnString error_message;
         error_message << "Illegal MySQL variables, the MaterializeMySQL engine requires ";
@@ -167,7 +170,7 @@ void MaterializeMySQLSyncThread::synchronization()
     try
     {
         MaterializeMetadata metadata(
-            DatabaseCatalog::instance().getDatabase(database_name)->getMetadataPath() + "/.metadata");
+            DatabaseCatalog::instance().getDatabase(database_name)->getMetadataPath() + "/.metadata", getContext()->getSettingsRef());
         bool need_reconnect = true;
 
         Stopwatch watch;
@@ -240,7 +243,7 @@ void MaterializeMySQLSyncThread::assertMySQLAvailable()
 {
     try
     {
-        checkMySQLVariables(pool.get());
+        checkMySQLVariables(pool.get(), getContext()->getSettingsRef());
     }
     catch (const mysqlxx::ConnectionFailed & e)
     {
@@ -326,9 +329,10 @@ static inline void dumpDataForTables(
             tryToExecuteQuery(query_prefix + " " + iterator->second, query_context, database_name, comment); /// create table.
 
             auto out = std::make_shared<CountingBlockOutputStream>(getTableOutput(database_name, table_name, query_context));
+            StreamSettings mysql_input_stream_settings(context->getSettingsRef());
             MySQLBlockInputStream input(
                 connection, "SELECT * FROM " + backQuoteIfNeed(mysql_database_name) + "." + backQuoteIfNeed(table_name),
-                out->getHeader(), DEFAULT_BLOCK_SIZE);
+                out->getHeader(), mysql_input_stream_settings);
 
             Stopwatch watch;
             copyData(input, *out, is_cancelled);
@@ -375,7 +379,7 @@ bool MaterializeMySQLSyncThread::prepareSynchronized(MaterializeMetadata & metad
 
             opened_transaction = false;
 
-            checkMySQLVariables(connection);
+            checkMySQLVariables(connection, getContext()->getSettingsRef());
             std::unordered_map<String, String> need_dumping_tables;
             metadata.startReplication(connection, mysql_database_name, opened_transaction, need_dumping_tables);
 

src/Dictionaries/MySQLDictionarySource.cpp

@@ -4,9 +4,15 @@
 #include "DictionarySourceFactory.h"
 #include "DictionaryStructure.h"
 #include "registerDictionaries.h"
+#include <Core/Settings.h>
+#include <Interpreters/Context.h>
 
 namespace DB
 {
+
+[[maybe_unused]]
+static const size_t default_num_tries_on_connection_loss = 3;
+
 namespace ErrorCodes
 {
     extern const int SUPPORT_IS_DISABLED;
@@ -14,20 +20,20 @@ namespace ErrorCodes
 
 void registerDictionarySourceMysql(DictionarySourceFactory & factory)
 {
-    auto create_table_source = [=](const DictionaryStructure & dict_struct,
+    auto create_table_source = [=]([[maybe_unused]] const DictionaryStructure & dict_struct,
-                                 const Poco::Util::AbstractConfiguration & config,
+                                   [[maybe_unused]] const Poco::Util::AbstractConfiguration & config,
-                                 const std::string & config_prefix,
+                                   [[maybe_unused]] const std::string & config_prefix,
-                                 Block & sample_block,
+                                   [[maybe_unused]] Block & sample_block,
-                                 ContextPtr /* context */,
+                                   [[maybe_unused]] ContextPtr context,
                                  const std::string & /* default_database */,
                                  bool /* check_config */) -> DictionarySourcePtr {
 #if USE_MYSQL
-        return std::make_unique<MySQLDictionarySource>(dict_struct, config, config_prefix + ".mysql", sample_block);
+        StreamSettings mysql_input_stream_settings(context->getSettingsRef()
+            , config.getBool(config_prefix + ".mysql.close_connection", false) || config.getBool(config_prefix + ".mysql.share_connection", false)
+            , false
+            , config.getBool(config_prefix + ".mysql.fail_on_connection_loss", false) ? 1 : default_num_tries_on_connection_loss);
+        return std::make_unique<MySQLDictionarySource>(dict_struct, config, config_prefix + ".mysql", sample_block, mysql_input_stream_settings);
 #else
-        (void)dict_struct;
-        (void)config;
-        (void)config_prefix;
-        (void)sample_block;
         throw Exception(ErrorCodes::SUPPORT_IS_DISABLED,
             "Dictionary source of type `mysql` is disabled because ClickHouse was built without mysql support.");
 #endif
@@ -45,22 +51,21 @@ void registerDictionarySourceMysql(DictionarySourceFactory & factory)
 #    include <IO/WriteHelpers.h>
 #    include <common/LocalDateTime.h>
 #    include <common/logger_useful.h>
-#    include <Formats/MySQLBlockInputStream.h>
 #    include "readInvalidateQuery.h"
 #    include <mysqlxx/Exception.h>
 #    include <mysqlxx/PoolFactory.h>
+#    include <Core/Settings.h>
 
 namespace DB
 {
-static const UInt64 max_block_size = 8192;
-static const size_t default_num_tries_on_connection_loss = 3;
 
 
 MySQLDictionarySource::MySQLDictionarySource(
     const DictionaryStructure & dict_struct_,
     const Poco::Util::AbstractConfiguration & config,
     const std::string & config_prefix,
-    const Block & sample_block_)
+    const Block & sample_block_,
+    const StreamSettings & settings_)
     : log(&Poco::Logger::get("MySQLDictionarySource"))
     , update_time{std::chrono::system_clock::from_time_t(0)}
     , dict_struct{dict_struct_}
@@ -74,10 +79,7 @@ MySQLDictionarySource::MySQLDictionarySource(
     , query_builder{dict_struct, db, "", table, where, IdentifierQuotingStyle::Backticks}
     , load_all_query{query_builder.composeLoadAllQuery()}
     , invalidate_query{config.getString(config_prefix + ".invalidate_query", "")}
-    , close_connection(
+    , settings(settings_)
-            config.getBool(config_prefix + ".close_connection", false) || config.getBool(config_prefix + ".share_connection", false))
-    , max_tries_for_mysql_block_input_stream(
-            config.getBool(config_prefix + ".fail_on_connection_loss", false) ? 1 : default_num_tries_on_connection_loss)
 {
 }
 
@@ -98,8 +100,7 @@ MySQLDictionarySource::MySQLDictionarySource(const MySQLDictionarySource & other
     , last_modification{other.last_modification}
     , invalidate_query{other.invalidate_query}
     , invalidate_query_response{other.invalidate_query_response}
-    , close_connection{other.close_connection}
+    , settings(other.settings)
-    , max_tries_for_mysql_block_input_stream{other.max_tries_for_mysql_block_input_stream}
 {
 }
 
@@ -122,7 +123,7 @@ std::string MySQLDictionarySource::getUpdateFieldAndDate()
 BlockInputStreamPtr MySQLDictionarySource::loadFromQuery(const String & query)
 {
     return std::make_shared<MySQLWithFailoverBlockInputStream>(
-            pool, query, sample_block, max_block_size, close_connection, false, max_tries_for_mysql_block_input_stream);
+            pool, query, sample_block, settings);
 }
 
 BlockInputStreamPtr MySQLDictionarySource::loadAll()
@@ -245,7 +246,7 @@ LocalDateTime MySQLDictionarySource::getLastModification(mysqlxx::Pool::Entry &
                 ++fetched_rows;
         }
 
-        if (close_connection && allow_connection_closure)
+        if (settings.auto_close && allow_connection_closure)
         {
             connection.disconnect();
         }
@@ -269,7 +270,7 @@ std::string MySQLDictionarySource::doInvalidateQuery(const std::string & request
     Block invalidate_sample_block;
     ColumnPtr column(ColumnString::create());
     invalidate_sample_block.insert(ColumnWithTypeAndName(column, std::make_shared<DataTypeString>(), "Sample Block"));
-    MySQLBlockInputStream block_input_stream(pool->get(), request, invalidate_sample_block, 1, close_connection);
+    MySQLBlockInputStream block_input_stream(pool->get(), request, invalidate_sample_block, settings);
     return readInvalidateQuery(block_input_stream);
 }
 

src/Dictionaries/MySQLDictionarySource.h

@@ -12,7 +12,7 @@
 #    include "DictionaryStructure.h"
 #    include "ExternalQueryBuilder.h"
 #    include "IDictionarySource.h"
-
+#    include <Formats/MySQLBlockInputStream.h>
 
 namespace Poco
 {
@@ -35,7 +35,8 @@ public:
         const DictionaryStructure & dict_struct_,
         const Poco::Util::AbstractConfiguration & config,
         const String & config_prefix,
-        const Block & sample_block_);
+        const Block & sample_block_,
+        const StreamSettings & settings_);
 
     /// copy-constructor is provided in order to support cloneability
     MySQLDictionarySource(const MySQLDictionarySource & other);
@@ -87,8 +88,7 @@ private:
     LocalDateTime last_modification;
     std::string invalidate_query;
     mutable std::string invalidate_query_response;
-    const bool close_connection;
+    const StreamSettings settings;
-    const size_t max_tries_for_mysql_block_input_stream;
 };
 
 }

src/Formats/MySQLBlockInputStream.cpp

@@ -30,6 +30,15 @@ namespace ErrorCodes
     extern const int NOT_IMPLEMENTED;
 }
 
+StreamSettings::StreamSettings(const Settings & settings, bool auto_close_, bool fetch_by_name_, size_t max_retry_)
+    : max_read_mysql_row_nums((settings.external_storage_max_read_rows) ? settings.external_storage_max_read_rows : settings.max_block_size)
+    , max_read_mysql_bytes_size(settings.external_storage_max_read_bytes)
+    , auto_close(auto_close_)
+    , fetch_by_name(fetch_by_name_)
+    , default_num_tries_on_connection_loss(max_retry_)
+{
+}
+
 MySQLBlockInputStream::Connection::Connection(
     const mysqlxx::PoolWithFailover::Entry & entry_,
     const std::string & query_str)
@@ -44,29 +53,19 @@ MySQLBlockInputStream::MySQLBlockInputStream(
     const mysqlxx::PoolWithFailover::Entry & entry,
     const std::string & query_str,
     const Block & sample_block,
-    const UInt64 max_block_size_,
+    const StreamSettings & settings_)
-    const bool auto_close_,
-    const bool fetch_by_name_)
     : log(&Poco::Logger::get("MySQLBlockInputStream"))
     , connection{std::make_unique<Connection>(entry, query_str)}
-    , max_block_size{max_block_size_}
+    , settings{std::make_unique<StreamSettings>(settings_)}
-    , auto_close{auto_close_}
-    , fetch_by_name(fetch_by_name_)
 {
     description.init(sample_block);
     initPositionMappingFromQueryResultStructure();
 }
 
 /// For descendant MySQLWithFailoverBlockInputStream
-MySQLBlockInputStream::MySQLBlockInputStream(
+    MySQLBlockInputStream::MySQLBlockInputStream(const Block &sample_block_, const StreamSettings & settings_)
-    const Block & sample_block_,
-    UInt64 max_block_size_,
-    bool auto_close_,
-    bool fetch_by_name_)
     : log(&Poco::Logger::get("MySQLBlockInputStream"))
-    , max_block_size(max_block_size_)
+    , settings(std::make_unique<StreamSettings>(settings_))
-    , auto_close(auto_close_)
-    , fetch_by_name(fetch_by_name_)
 {
     description.init(sample_block_);
 }
@@ -76,14 +75,10 @@ MySQLWithFailoverBlockInputStream::MySQLWithFailoverBlockInputStream(
     mysqlxx::PoolWithFailoverPtr pool_,
     const std::string & query_str_,
     const Block & sample_block_,
-    const UInt64 max_block_size_,
+    const StreamSettings & settings_)
-    const bool auto_close_,
+: MySQLBlockInputStream(sample_block_, settings_)
-    const bool fetch_by_name_,
+, pool(pool_)
-    const size_t max_tries_)
+, query_str(query_str_)
-    : MySQLBlockInputStream(sample_block_, max_block_size_, auto_close_, fetch_by_name_)
-    , pool(pool_)
-    , query_str(query_str_)
-    , max_tries(max_tries_)
 {
 }
 
@@ -101,12 +96,12 @@ void MySQLWithFailoverBlockInputStream::readPrefix()
         }
         catch (const mysqlxx::ConnectionLost & ecl)  /// There are two retriable failures: CR_SERVER_GONE_ERROR, CR_SERVER_LOST
         {
-            LOG_WARNING(log, "Failed connection ({}/{}). Trying to reconnect... (Info: {})", count_connect_attempts, max_tries, ecl.displayText());
+            LOG_WARNING(log, "Failed connection ({}/{}). Trying to reconnect... (Info: {})", count_connect_attempts, settings->default_num_tries_on_connection_loss, ecl.displayText());
         }
 
-        if (++count_connect_attempts > max_tries)
+        if (++count_connect_attempts > settings->default_num_tries_on_connection_loss)
         {
-            LOG_ERROR(log, "Failed to create connection to MySQL. ({}/{})", count_connect_attempts, max_tries);
+            LOG_ERROR(log, "Failed to create connection to MySQL. ({}/{})", count_connect_attempts, settings->default_num_tries_on_connection_loss);
             throw;
         }
     }
@@ -118,45 +113,57 @@ namespace
 {
     using ValueType = ExternalResultDescription::ValueType;
 
-    void insertValue(const IDataType & data_type, IColumn & column, const ValueType type, const mysqlxx::Value & value)
+    void insertValue(const IDataType & data_type, IColumn & column, const ValueType type, const mysqlxx::Value & value, size_t & read_bytes_size)
     {
         switch (type)
         {
             case ValueType::vtUInt8:
                 assert_cast<ColumnUInt8 &>(column).insertValue(value.getUInt());
+                read_bytes_size += 1;
                 break;
             case ValueType::vtUInt16:
                 assert_cast<ColumnUInt16 &>(column).insertValue(value.getUInt());
+                read_bytes_size += 2;
                 break;
             case ValueType::vtUInt32:
                 assert_cast<ColumnUInt32 &>(column).insertValue(value.getUInt());
+                read_bytes_size += 4;
                 break;
             case ValueType::vtUInt64:
                 assert_cast<ColumnUInt64 &>(column).insertValue(value.getUInt());
+                read_bytes_size += 8;
                 break;
             case ValueType::vtInt8:
                 assert_cast<ColumnInt8 &>(column).insertValue(value.getInt());
+                read_bytes_size += 1;
                 break;
             case ValueType::vtInt16:
                 assert_cast<ColumnInt16 &>(column).insertValue(value.getInt());
+                read_bytes_size += 2;
                 break;
             case ValueType::vtInt32:
                 assert_cast<ColumnInt32 &>(column).insertValue(value.getInt());
+                read_bytes_size += 4;
                 break;
             case ValueType::vtInt64:
                 assert_cast<ColumnInt64 &>(column).insertValue(value.getInt());
+                read_bytes_size += 8;
                 break;
             case ValueType::vtFloat32:
                 assert_cast<ColumnFloat32 &>(column).insertValue(value.getDouble());
+                read_bytes_size += 4;
                 break;
             case ValueType::vtFloat64:
                 assert_cast<ColumnFloat64 &>(column).insertValue(value.getDouble());
+                read_bytes_size += 8;
                 break;
             case ValueType::vtString:
                 assert_cast<ColumnString &>(column).insertData(value.data(), value.size());
+                read_bytes_size += assert_cast<ColumnString &>(column).byteSize();
                 break;
             case ValueType::vtDate:
                 assert_cast<ColumnUInt16 &>(column).insertValue(UInt16(value.getDate().getDayNum()));
+                read_bytes_size += 2;
                 break;
             case ValueType::vtDateTime:
             {
@@ -166,10 +173,12 @@ namespace
                 if (time < 0)
                     time = 0;
                 assert_cast<ColumnUInt32 &>(column).insertValue(time);
+                read_bytes_size += 4;
                 break;
             }
             case ValueType::vtUUID:
                 assert_cast<ColumnUInt128 &>(column).insert(parse<UUID>(value.data(), value.size()));
+                read_bytes_size += assert_cast<ColumnUInt128 &>(column).byteSize();
                 break;
             case ValueType::vtDateTime64:[[fallthrough]];
             case ValueType::vtDecimal32: [[fallthrough]];
@@ -179,10 +188,12 @@ namespace
             {
                 ReadBuffer buffer(const_cast<char *>(value.data()), value.size(), 0);
                 data_type.getDefaultSerialization()->deserializeWholeText(column, buffer, FormatSettings{});
+                read_bytes_size += column.sizeOfValueIfFixed();
                 break;
             }
             case ValueType::vtFixedString:
                 assert_cast<ColumnFixedString &>(column).insertData(value.data(), value.size());
+                read_bytes_size += column.sizeOfValueIfFixed();
                 break;
             default:
                 throw Exception("Unsupported value type", ErrorCodes::NOT_IMPLEMENTED);
@@ -198,7 +209,7 @@ Block MySQLBlockInputStream::readImpl()
     auto row = connection->result.fetch();
     if (!row)
     {
-        if (auto_close)
+        if (settings->auto_close)
            connection->entry.disconnect();
 
         return {};
@@ -209,6 +220,8 @@ Block MySQLBlockInputStream::readImpl()
         columns[i] = description.sample_block.getByPosition(i).column->cloneEmpty();
 
     size_t num_rows = 0;
+    size_t read_bytes_size = 0;
+
     while (row)
     {
         for (size_t index = 0; index < position_mapping.size(); ++index)
@@ -224,12 +237,12 @@ Block MySQLBlockInputStream::readImpl()
                 {
                     ColumnNullable & column_nullable = assert_cast<ColumnNullable &>(*columns[index]);
                     const auto & data_type = assert_cast<const DataTypeNullable &>(*sample.type);
-                    insertValue(*data_type.getNestedType(), column_nullable.getNestedColumn(), description.types[index].first, value);
+                    insertValue(*data_type.getNestedType(), column_nullable.getNestedColumn(), description.types[index].first, value, read_bytes_size);
                     column_nullable.getNullMapData().emplace_back(false);
                 }
                 else
                 {
-                    insertValue(*sample.type, *columns[index], description.types[index].first, value);
+                    insertValue(*sample.type, *columns[index], description.types[index].first, value, read_bytes_size);
                 }
             }
             else
@@ -245,7 +258,7 @@ Block MySQLBlockInputStream::readImpl()
         }
 
         ++num_rows;
-        if (num_rows == max_block_size)
+        if (num_rows == settings->max_read_mysql_row_nums || (settings->max_read_mysql_bytes_size && read_bytes_size >= settings->max_read_mysql_bytes_size))
             break;
 
         row = connection->result.fetch();
@@ -257,7 +270,7 @@ void MySQLBlockInputStream::initPositionMappingFromQueryResultStructure()
 {
     position_mapping.resize(description.sample_block.columns());
 
-    if (!fetch_by_name)
+    if (!settings->fetch_by_name)
     {
         if (description.sample_block.columns() != connection->result.getNumFields())
             throw Exception{"mysqlxx::UseQueryResult contains " + toString(connection->result.getNumFields()) + " columns while "

src/Formats/MySQLBlockInputStream.h

@@ -6,11 +6,24 @@
 #include <mysqlxx/PoolWithFailover.h>
 #include <mysqlxx/Query.h>
 #include <Core/ExternalResultDescription.h>
-
+#include <Core/Settings.h>
 
 namespace DB
 {
 
+struct StreamSettings
+{
+    /// Check if setting is enabled, otherwise use common `max_block_size` setting.
+    size_t max_read_mysql_row_nums;
+    size_t max_read_mysql_bytes_size;
+    bool auto_close;
+    bool fetch_by_name;
+    size_t default_num_tries_on_connection_loss;
+
+    StreamSettings(const Settings & settings, bool auto_close_ = false, bool fetch_by_name_ = false, size_t max_retry_ = 5);
+
+};
+
 /// Allows processing results of a MySQL query as a sequence of Blocks, simplifies chaining
 class MySQLBlockInputStream : public IBlockInputStream
 {
@@ -19,16 +32,14 @@ public:
         const mysqlxx::PoolWithFailover::Entry & entry,
         const std::string & query_str,
         const Block & sample_block,
-        const UInt64 max_block_size_,
+        const StreamSettings & settings_);
-        const bool auto_close_ = false,
-        const bool fetch_by_name_ = false);
 
     String getName() const override { return "MySQL"; }
 
     Block getHeader() const override { return description.sample_block.cloneEmpty(); }
 
 protected:
-    MySQLBlockInputStream(const Block & sample_block_, UInt64 max_block_size_, bool auto_close_, bool fetch_by_name_);
+    MySQLBlockInputStream(const Block & sample_block_, const StreamSettings & settings);
     Block readImpl() override;
     void initPositionMappingFromQueryResultStructure();
 
@@ -44,9 +55,7 @@ protected:
     Poco::Logger * log;
     std::unique_ptr<Connection> connection;
 
-    const UInt64 max_block_size;
+    const std::unique_ptr<StreamSettings> settings;
-    const bool auto_close;
-    const bool fetch_by_name;
     std::vector<size_t> position_mapping;
     ExternalResultDescription description;
 };
@@ -57,23 +66,18 @@ protected:
 class MySQLWithFailoverBlockInputStream final : public MySQLBlockInputStream
 {
 public:
-    static constexpr inline auto MAX_TRIES_MYSQL_CONNECT = 5;
 
     MySQLWithFailoverBlockInputStream(
         mysqlxx::PoolWithFailoverPtr pool_,
         const std::string & query_str_,
         const Block & sample_block_,
-        const UInt64 max_block_size_,
+        const StreamSettings & settings_);
-        const bool auto_close_ = false,
-        const bool fetch_by_name_ = false,
-        const size_t max_tries_ = MAX_TRIES_MYSQL_CONNECT);
 
 private:
     void readPrefix() override;
 
     mysqlxx::PoolWithFailoverPtr pool;
     std::string query_str;
-    size_t max_tries;
 };
 
 }

src/Storages/StorageMySQL.cpp

@@ -71,7 +71,7 @@ Pipe StorageMySQL::read(
     SelectQueryInfo & query_info_,
     ContextPtr context_,
     QueryProcessingStage::Enum /*processed_stage*/,
-    size_t max_block_size_,
+    size_t /*max_block_size*/,
     unsigned)
 {
     metadata_snapshot->check(column_names_, getVirtuals(), getStorageID());
@@ -95,8 +95,10 @@ Pipe StorageMySQL::read(
         sample_block.insert({ column_data.type, column_data.name });
     }
 
+
+    StreamSettings mysql_input_stream_settings(context_->getSettingsRef(), true, false);
     return Pipe(std::make_shared<SourceFromInputStream>(
-            std::make_shared<MySQLWithFailoverBlockInputStream>(pool, query, sample_block, max_block_size_, /* auto_close = */ true)));
+            std::make_shared<MySQLWithFailoverBlockInputStream>(pool, query, sample_block, mysql_input_stream_settings)));
 }
 
 

src/TableFunctions/TableFunctionMySQL.cpp

@@ -79,7 +79,7 @@ void TableFunctionMySQL::parseArguments(const ASTPtr & ast_function, ContextPtr
 ColumnsDescription TableFunctionMySQL::getActualTableStructure(ContextPtr context) const
 {
     const auto & settings = context->getSettingsRef();
-    const auto tables_and_columns = fetchTablesColumnsList(*pool, remote_database_name, {remote_table_name}, settings.external_table_functions_use_nulls, settings.mysql_datatypes_support_level);
+    const auto tables_and_columns = fetchTablesColumnsList(*pool, remote_database_name, {remote_table_name}, settings, settings.mysql_datatypes_support_level);
 
     const auto columns = tables_and_columns.find(remote_table_name);
     if (columns == tables_and_columns.end())

tests/integration/test_materialize_mysql_database/configs/users_disable_bytes_settings.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0"?>
+<yandex>
+    <profiles>
+        <default>
+            <allow_experimental_database_materialize_mysql>1</allow_experimental_database_materialize_mysql>
+            <default_database_engine>Atomic</default_database_engine>
+            <external_storage_max_read_rows>1</external_storage_max_read_rows>
+            <external_storage_max_read_bytes>0</external_storage_max_read_bytes>
+        </default>
+    </profiles>
+
+    <users>
+        <default>
+            <password></password>
+            <networks incl="networks" replace="replace">
+                <ip>::/0</ip>
+            </networks>
+            <profile>default</profile>
+        </default>
+    </users>
+</yandex>

tests/integration/test_materialize_mysql_database/configs/users_disable_rows_settings.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0"?>
+<yandex>
+    <profiles>
+        <default>
+            <allow_experimental_database_materialize_mysql>1</allow_experimental_database_materialize_mysql>
+            <default_database_engine>Atomic</default_database_engine>
+            <external_storage_max_read_rows>0</external_storage_max_read_rows>
+            <external_storage_max_read_bytes>1</external_storage_max_read_bytes>
+        </default>
+    </profiles>
+
+    <users>
+        <default>
+            <password></password>
+            <networks incl="networks" replace="replace">
+                <ip>::/0</ip>
+            </networks>
+            <profile>default</profile>
+        </default>
+    </users>
+</yandex>

tests/integration/test_materialize_mysql_database/materialize_with_ddl.py

@@ -842,3 +842,19 @@ def system_tables_test(clickhouse_node, mysql_node, service_name):
     mysql_node.query("CREATE TABLE system_tables_test.test (id int NOT NULL PRIMARY KEY) ENGINE=InnoDB")
     clickhouse_node.query("CREATE DATABASE system_tables_test ENGINE = MaterializeMySQL('{}:3306', 'system_tables_test', 'root', 'clickhouse')".format(service_name))
     check_query(clickhouse_node, "SELECT partition_key, sorting_key, primary_key FROM system.tables WHERE database = 'system_tables_test' AND name = 'test'", "intDiv(id, 4294967)\tid\tid\n")
+
+def mysql_settings_test(clickhouse_node, mysql_node, service_name):
+    mysql_node.query("DROP DATABASE IF EXISTS test_database")
+    clickhouse_node.query("DROP DATABASE IF EXISTS test_database")
+    mysql_node.query("CREATE DATABASE test_database")
+    mysql_node.query("CREATE TABLE test_database.a (id INT(11) NOT NULL PRIMARY KEY, value VARCHAR(255))")
+    mysql_node.query("INSERT INTO test_database.a VALUES(1, 'foo')")
+    mysql_node.query("INSERT INTO test_database.a VALUES(2, 'bar')")
+
+    clickhouse_node.query("CREATE DATABASE test_database ENGINE = MaterializeMySQL('{}:3306', 'test_database', 'root', 'clickhouse')".format(service_name))
+    check_query(clickhouse_node, "SELECT COUNT() FROM test_database.a FORMAT TSV", "2\n")
+
+    assert clickhouse_node.query("SELECT COUNT(DISTINCT  blockNumber()) FROM test_database.a FORMAT TSV") == "2\n"
+
+    clickhouse_node.query("DROP DATABASE test_database")
+    mysql_node.query("DROP DATABASE test_database")

tests/integration/test_materialize_mysql_database/test.py

@@ -16,7 +16,8 @@ cluster = ClickHouseCluster(__file__)
 
 node_db_ordinary = cluster.add_instance('node1', user_configs=["configs/users.xml"], with_mysql=False, stay_alive=True)
 node_db_atomic = cluster.add_instance('node2', user_configs=["configs/users_db_atomic.xml"], with_mysql=False, stay_alive=True)
-
+node_disable_bytes_settings = cluster.add_instance('node3', user_configs=["configs/users_disable_bytes_settings.xml"], with_mysql=False, stay_alive=True)
+node_disable_rows_settings = cluster.add_instance('node4', user_configs=["configs/users_disable_rows_settings.xml"], with_mysql=False, stay_alive=True)
 
 @pytest.fixture(scope="module")
 def started_cluster():
@@ -289,5 +290,12 @@ def test_multi_table_update(started_cluster, started_mysql_8_0, started_mysql_5_
 
 
 @pytest.mark.parametrize(('clickhouse_node'), [node_db_ordinary, node_db_ordinary])
-def test_system_tables_table(started_cluster, started_mysql_8_0, clickhouse_node):
+def test_system_tables_table(started_cluster, started_mysql_8_0, started_mysql_5_7, clickhouse_node):
+    materialize_with_ddl.system_tables_test(clickhouse_node, started_mysql_5_7, "mysql1")
     materialize_with_ddl.system_tables_test(clickhouse_node, started_mysql_8_0, "mysql8_0")
+
+
+@pytest.mark.parametrize(('clickhouse_node'), [node_disable_bytes_settings, node_disable_rows_settings])
+def test_mysql_settings(started_cluster, started_mysql_8_0, started_mysql_5_7, clickhouse_node):
+    materialize_with_ddl.mysql_settings_test(clickhouse_node, started_mysql_5_7, "mysql1")
+    materialize_with_ddl.mysql_settings_test(clickhouse_node, started_mysql_8_0, "mysql8_0")

tests/integration/test_storage_mysql/configs/users.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0"?>
+<yandex>
+    <profiles>
+        <default>
+            <max_block_size>2</max_block_size>
+        </default>
+    </profiles>
+
+    <users>
+        <default>
+            <password></password>
+            <networks incl="networks" replace="replace">
+                <ip>::/0</ip>
+            </networks>
+            <profile>default</profile>
+        </default>
+    </users>
+</yandex>

tests/integration/test_storage_mysql/test.py

@@ -9,6 +9,7 @@ cluster = ClickHouseCluster(__file__)
 
 node1 = cluster.add_instance('node1', main_configs=['configs/remote_servers.xml'], with_mysql=True)
 node2 = cluster.add_instance('node2', main_configs=['configs/remote_servers.xml'], with_mysql_cluster=True)
+node3 = cluster.add_instance('node3', main_configs=['configs/remote_servers.xml'], user_configs=['configs/users.xml'], with_mysql=True)
 
 create_table_sql_template = """
     CREATE TABLE `clickhouse`.`{}` (
@@ -260,6 +261,25 @@ def test_mysql_distributed(started_cluster):
     assert(result == 'host2\nhost4\n' or result == 'host3\nhost4\n')
 
 
+def test_external_settings(started_cluster):
+    table_name = 'test_external_settings'
+    conn = get_mysql_conn()
+    create_mysql_table(conn, table_name)
+
+    node3.query('''
+CREATE TABLE {}(id UInt32, name String, age UInt32, money UInt32) ENGINE = MySQL('mysql1:3306', 'clickhouse', '{}', 'root', 'clickhouse');
+'''.format(table_name, table_name))
+    node3.query(
+        "INSERT INTO {}(id, name, money) select number, concat('name_', toString(number)), 3 from numbers(100) ".format(
+            table_name))
+    assert node3.query("SELECT count() FROM {}".format(table_name)).rstrip() == '100'
+    assert node3.query("SELECT sum(money) FROM {}".format(table_name)).rstrip() == '300'
+    node3.query("select value from system.settings where name = 'max_block_size' FORMAT TSV") == "2\n"
+    node3.query("select value from system.settings where name = 'external_storage_max_read_rows' FORMAT TSV") == "0\n"
+    assert node3.query("SELECT COUNT(DISTINCT blockNumber()) FROM {} FORMAT TSV".format(table_name)) == '50\n'
+    conn.close()
+
+
 if __name__ == '__main__':
     with contextmanager(started_cluster)() as cluster:
         for name, instance in list(cluster.instances.items()):