Merge

2024-11-27 18:12:02 +00:00 · 2016-03-08 20:51:32 +03:00 · 2016-03-08 20:51:32 +03:00 · de920939e2
commit de920939e2
parent 44c9de8873 9d3eb0dffc
45 changed files with 614 additions and 296 deletions
--- a/dbms/CMakeLists.txt
+++ b/dbms/CMakeLists.txt
@ -56,6 +56,7 @@ add_library (dbms
 	include/DB/Parsers/ASTExpressionList.h
 	include/DB/Parsers/ASTQueryWithOutput.h
 	include/DB/Parsers/ParserSelectQuery.h
+	include/DB/Parsers/ParserTableExpression.h
 	include/DB/Parsers/ParserUseQuery.h
 	include/DB/Parsers/ASTShowTablesQuery.h
 	include/DB/Parsers/ASTFunction.h
@ -726,6 +727,7 @@ add_library (dbms
 	src/Parsers/ParserQueryWithOutput.cpp
 	src/Parsers/ParserCreateQuery.cpp
 	src/Parsers/ParserSelectQuery.cpp
+	src/Parsers/ParserTableExpression.cpp
 	src/Parsers/ParserJoin.cpp
 	src/Parsers/ParserInsertQuery.cpp
 	src/Parsers/ParserDropQuery.cpp
--- a/dbms/include/DB/DataStreams/UnionBlockInputStream.h
+++ b/dbms/include/DB/DataStreams/UnionBlockInputStream.h
@ -67,14 +67,19 @@ struct OutputData<StreamUnionMode::ExtraInfo>
 template <StreamUnionMode mode = StreamUnionMode::Basic>
 class UnionBlockInputStream : public IProfilingBlockInputStream
 {
+public:
+	using ExceptionCallback = std::function<void()>;
+
 private:
 	using Self = UnionBlockInputStream<mode>;

 public:
-	UnionBlockInputStream(BlockInputStreams inputs, BlockInputStreamPtr additional_input_at_end, size_t max_threads) :
+	UnionBlockInputStream(BlockInputStreams inputs, BlockInputStreamPtr additional_input_at_end, size_t max_threads,
+		ExceptionCallback exception_callback_ = ExceptionCallback()) :
 		output_queue(std::min(inputs.size(), max_threads)),
 		handler(*this),
-		processor(inputs, additional_input_at_end, max_threads, handler)
+		processor(inputs, additional_input_at_end, max_threads, handler),
+		exception_callback(exception_callback_)
 	{
 		children = inputs;
 		if (additional_input_at_end)
@ -203,7 +208,11 @@ protected:
 		output_queue.pop(received_payload);

 		if (received_payload.exception)
+		{
+			if (exception_callback)
+				exception_callback();
 			std::rethrow_exception(received_payload.exception);
+		}

 		if (!received_payload.block)
 			all_read = true;
@ -299,6 +308,8 @@ private:
 	Handler handler;
 	ParallelInputsProcessor<Handler, mode> processor;

+	ExceptionCallback exception_callback;
+
 	Payload received_payload;

 	bool started = false;
--- a/dbms/include/DB/Dictionaries/Embedded/RegionsNames.h
+++ b/dbms/include/DB/Dictionaries/Embedded/RegionsNames.h
@ -1,6 +1,6 @@
 #pragma once

-#include <google/dense_hash_map>
+#include <sparsehash/dense_hash_map>

 #include <Poco/File.h>
 #include <Poco/NumberParser.h>
--- a/dbms/include/DB/Interpreters/Cluster.h
+++ b/dbms/include/DB/Interpreters/Cluster.h
@ -121,6 +121,7 @@ private:
 	size_t local_shard_count = 0;
 };

+
 class Clusters
 {
 public:
--- a/dbms/include/DB/Interpreters/ExpressionAnalyzer.h
+++ b/dbms/include/DB/Interpreters/ExpressionAnalyzer.h
@ -271,7 +271,8 @@ private:
 	  * Установить has_aggregation = true, если есть GROUP BY или хотя бы одна агрегатная функция.
 	  */
 	void analyzeAggregation();
-	void getAggregates(ASTPtr ast, ExpressionActionsPtr & actions);
+	void getAggregates(const ASTPtr & ast, ExpressionActionsPtr & actions);
+	void assertNoAggregates(const ASTPtr & ast, const char * description);

 	/** Получить множество нужных столбцов для чтения из таблицы.
 	  * При этом, столбцы, указанные в ignored_names, считаются ненужными. И параметр ignored_names может модифицироваться.
--- a/dbms/include/DB/Parsers/ASTSelectQuery.h
+++ b/dbms/include/DB/Parsers/ASTSelectQuery.h
@ -49,7 +49,7 @@ public:
 	bool distinct = false;
 	ASTPtr select_expression_list;
 	ASTPtr database;
-	ASTPtr table;	/// Идентификатор, табличная функция или подзапрос (рекурсивно ASTSelectQuery)
+	ASTPtr table;	/// Имя таблицы, табличная функция или подзапрос (рекурсивно ASTSelectQuery)
 	bool array_join_is_left = false;	/// LEFT ARRAY JOIN
 	ASTPtr array_join_expression_list;	/// ARRAY JOIN
 	ASTPtr join;						/// Обычный (не ARRAY) JOIN.
--- a/dbms/include/DB/Parsers/ParserTableExpression.h
+++ b/dbms/include/DB/Parsers/ParserTableExpression.h
@ -0,0 +1,20 @@
+#pragma once
+
+#include <DB/Parsers/IParserBase.h>
+
+
+namespace DB
+{
+
+/** Имя таблицы (с или без имени БД), табличная функция, подзапрос.
+  * Без модификаторов FINAL, SAMPLE и т. п.
+  * Без алиаса.
+  */
+class ParserTableExpression : public IParserBase
+{
+protected:
+	const char * getName() const { return "table or subquery or table function"; }
+	bool parseImpl(Pos & pos, Pos end, ASTPtr & node, Pos & max_parsed_pos, Expected & expected);
+};
+
+}
--- a/dbms/include/DB/Storages/MergeTree/MergeTreeData.h
+++ b/dbms/include/DB/Storages/MergeTree/MergeTreeData.h
@ -252,16 +252,18 @@ public:
 			return NameAndTypePair("_part", new DataTypeString);
 		if (column_name == "_part_index")
 			return NameAndTypePair("_part_index", new DataTypeUInt64);
+		if (column_name == "_sample_factor")
+			return NameAndTypePair("_sample_factor", new DataTypeFloat64);
+
 		return ITableDeclaration::getColumn(column_name);
 	}

 	bool hasColumn(const String & column_name) const override
 	{
-		if (column_name == "_part")
-			return true;
-		if (column_name == "_part_index")
-			return true;
-		return ITableDeclaration::hasColumn(column_name);
+		return ITableDeclaration::hasColumn(column_name)
+			|| column_name == "_part"
+			|| column_name == "_part_index"
+			|| column_name == "_sample_factor";
 	}

 	String getFullPath() const { return full_path; }
--- a/dbms/include/DB/Storages/MergeTree/MergeTreeDataSelectExecutor.h
+++ b/dbms/include/DB/Storages/MergeTree/MergeTreeDataSelectExecutor.h
@ -17,7 +17,6 @@ public:
 	MergeTreeDataSelectExecutor(MergeTreeData & data_);

 	/** При чтении, выбирается набор кусков, покрывающий нужный диапазон индекса.
-	  * Если inout_part_index != nullptr, из этого счетчика берутся значения для виртуального столбца _part_index.
 	  * max_block_number_to_read - если не ноль - не читать все куски, у которых правая граница больше этого порога.
 	  */
 	BlockInputStreams read(
@ -28,7 +27,7 @@ public:
 		QueryProcessingStage::Enum & processed_stage,
 		size_t max_block_size,
 		unsigned threads,
-		size_t * inout_part_index,
+		size_t * inout_part_index,	/// Если не nullptr, из этого счетчика берутся значения для виртуального столбца _part_index.
 		Int64 max_block_number_to_read) const;

 private:
--- a/dbms/include/DB/Storages/MergeTree/MergeTreeThreadBlockInputStream.h
+++ b/dbms/include/DB/Storages/MergeTree/MergeTreeThreadBlockInputStream.h
@ -318,6 +318,7 @@ private:
 		const auto rows = block.rowsInFirstColumn();

 		/// add virtual columns
+		/// Кроме _sample_factor, который добавляется снаружи.
 		if (!virt_column_names.empty())
 		{
 			for (const auto & virt_column_name : virt_column_names)
--- a/dbms/include/DB/Storages/MergeTree/ReshardingWorker.h
+++ b/dbms/include/DB/Storages/MergeTree/ReshardingWorker.h
@ -155,7 +155,6 @@ private:
 	zkutil::RWLock createLock();
 	zkutil::RWLock createCoordinatorLock(const std::string & coordinator_id);

-	zkutil::SingleBarrier createSubscribeBarrier(const std::string & coordinator_id);
 	zkutil::SingleBarrier createCheckBarrier(const std::string & coordinator_id);
 	zkutil::SingleBarrier createOptOutBarrier(const std::string & coordinator_id, size_t count);
 	zkutil::SingleBarrier createRecoveryBarrier(const ReshardingJob & job);
--- a/dbms/include/DB/Storages/StorageMerge.h
+++ b/dbms/include/DB/Storages/StorageMerge.h
@ -45,8 +45,8 @@ public:
 	bool supportsIndexForIn() const override { return true; }

 	const NamesAndTypesList & getColumnsListImpl() const override { return *columns; }
-	NameAndTypePair getColumn(const String &column_name) const override;
-	bool hasColumn(const String &column_name) const override;
+	NameAndTypePair getColumn(const String & column_name) const override;
+	bool hasColumn(const String & column_name) const override;

 	BlockInputStreams read(
 		const Names & column_names,
--- a/dbms/include/DB/TableFunctions/TableFunctionMerge.h
+++ b/dbms/include/DB/TableFunctions/TableFunctionMerge.h
@ -72,11 +72,13 @@ private:
 			context.assertDatabaseExists(source_database);
 			const Tables & tables = context.getDatabases().at(source_database);
 			for (Tables::const_iterator it = tables.begin(); it != tables.end(); ++it)
+			{
 				if (table_name_regexp.match(it->first))
 				{
 					any_table = it->second;
 					break;
 				}
+			}
 		}

 		if (!any_table)
--- a/dbms/src/Core/ErrorCodes.cpp
+++ b/dbms/src/Core/ErrorCodes.cpp
@ -337,7 +337,8 @@ namespace ErrorCodes
 	extern const int RESHARDING_INVALID_QUERY = 331;
 	extern const int RESHARDING_INITIATOR_CHECK_FAILED = 332;
 	extern const int RWLOCK_ALREADY_HELD = 333;
-	extern const int BARRIER_TIMEOUT = 334;
+	extern const int RWLOCK_NO_SUCH_LOCK = 334;
+	extern const int BARRIER_TIMEOUT = 335;

 	extern const int KEEPER_EXCEPTION = 999;
 	extern const int POCO_EXCEPTION = 1000;
--- a/dbms/src/Interpreters/Cluster.cpp
+++ b/dbms/src/Interpreters/Cluster.cpp
@ -130,6 +130,9 @@ Cluster::Cluster(const Settings & settings, const String & cluster_name)
 	Poco::Util::AbstractConfiguration::Keys config_keys;
 	config.keys(cluster_name, config_keys);

+	if (config_keys.empty())
+		throw Exception("No cluster elements (shard, node) specified in config at path " + cluster_name, ErrorCodes::SHARD_HAS_NO_CONNECTIONS);
+
 	const auto & config_prefix = cluster_name + ".";

 	UInt32 current_shard_num = 1;
@ -374,7 +377,7 @@ void Cluster::assignName()
 	SHA512_Init(&ctx);

 	for (const auto & host : elements)
-		SHA512_Update(&ctx, reinterpret_cast<const void *>(host.data()), host.size());
+		SHA512_Update(&ctx, reinterpret_cast<const void *>(host.c_str()), host.size() + 1);

 	SHA512_Final(hash, &ctx);

--- a/dbms/src/Interpreters/ExpressionAnalyzer.cpp
+++ b/dbms/src/Interpreters/ExpressionAnalyzer.cpp
@ -68,6 +68,7 @@ namespace ErrorCodes
 	extern const int PARAMETERS_TO_AGGREGATE_FUNCTIONS_MUST_BE_LITERALS;
 	extern const int DUPLICATE_COLUMN;
 	extern const int FUNCTION_CANNOT_HAVE_PARAMETERS;
+	extern const int ILLEGAL_AGGREGATION;
 }


@ -128,7 +129,7 @@ bool functionIsInOrGlobalInOperator(const String & name)

 void ExpressionAnalyzer::init()
 {
-	select_query = typeid_cast<ASTSelectQuery *>(&*ast);
+	select_query = typeid_cast<ASTSelectQuery *>(ast.get());

 	/// В зависимости от профиля пользователя проверить наличие прав на выполнение
 	/// распределённых подзапросов внутри секций IN или JOIN и обработать эти подзапросы.
@ -292,18 +293,18 @@ void ExpressionAnalyzer::initGlobalSubqueries(ASTPtr & ast)
 	/// Рекурсивные вызовы. Не опускаемся в подзапросы.

 	for (auto & child : ast->children)
-		if (!typeid_cast<ASTSelectQuery *>(&*child))
+		if (!typeid_cast<ASTSelectQuery *>(child.get()))
 			initGlobalSubqueries(child);

 	/// Действия, выполняемые снизу вверх.

-	if (ASTFunction * node = typeid_cast<ASTFunction *>(&*ast))
+	if (ASTFunction * node = typeid_cast<ASTFunction *>(ast.get()))
 	{
 		/// Для GLOBAL IN.
 		if (do_global && (node->name == "globalIn" || node->name == "globalNotIn"))
 			addExternalStorage(node->arguments->children.at(1));
 	}
-	else if (ASTJoin * node = typeid_cast<ASTJoin *>(&*ast))
+	else if (ASTJoin * node = typeid_cast<ASTJoin *>(ast.get()))
 	{
 		/// Для GLOBAL JOIN.
 		if (do_global && node->locality == ASTJoin::Global)
@ -321,7 +322,7 @@ void ExpressionAnalyzer::findExternalTables(ASTPtr & ast)
 	/// Если идентификатор типа таблица
 	StoragePtr external_storage;

-	if (ASTIdentifier * node = typeid_cast<ASTIdentifier *>(&*ast))
+	if (ASTIdentifier * node = typeid_cast<ASTIdentifier *>(ast.get()))
 		if (node->kind == ASTIdentifier::Table)
 			if ((external_storage = context.tryGetExternalTable(node->name)))
 				external_tables[node->name] = external_storage;
@ -338,7 +339,7 @@ void ExpressionAnalyzer::addExternalStorage(ASTPtr & subquery_or_table_name)
 	if (!(storage && storage->isRemote()))
 		return;

-	if (const ASTIdentifier * table = typeid_cast<const ASTIdentifier *>(&*subquery_or_table_name))
+	if (const ASTIdentifier * table = typeid_cast<const ASTIdentifier *>(subquery_or_table_name.get()))
 	{
 		/// Если это уже внешняя таблица, ничего заполять не нужно. Просто запоминаем ее наличие.
 		if (external_tables.end() != external_tables.find(table->name))
@ -449,7 +450,7 @@ NamesAndTypesList::iterator ExpressionAnalyzer::findColumn(const String & name,
 /// Например, при ignore_levels=1 ast не может быть занесен в словарь, но его дети могут.
 void ExpressionAnalyzer::addASTAliases(ASTPtr & ast, int ignore_levels)
 {
-	ASTSelectQuery * select = typeid_cast<ASTSelectQuery *>(&*ast);
+	ASTSelectQuery * select = typeid_cast<ASTSelectQuery *>(ast.get());

 	/// Обход снизу-вверх. Не опускаемся в подзапросы.
 	for (auto & child : ast->children)
@ -461,7 +462,7 @@ void ExpressionAnalyzer::addASTAliases(ASTPtr & ast, int ignore_levels)
 		if (select && child == select->array_join_expression_list)
 			new_ignore_levels = 2;

-		if (!typeid_cast<ASTSelectQuery *>(&*child))
+		if (!typeid_cast<ASTSelectQuery *>(child.get()))
 			addASTAliases(child, new_ignore_levels);
 	}

@ -481,9 +482,9 @@ void ExpressionAnalyzer::addASTAliases(ASTPtr & ast, int ignore_levels)

 StoragePtr ExpressionAnalyzer::getTable()
 {
-	if (const ASTSelectQuery * select = typeid_cast<const ASTSelectQuery *>(&*ast))
+	if (const ASTSelectQuery * select = typeid_cast<const ASTSelectQuery *>(ast.get()))
 	{
-		if (select->table && !typeid_cast<const ASTSelectQuery *>(&*select->table) && !typeid_cast<const ASTFunction *>(&*select->table))
+		if (select->table && !typeid_cast<const ASTSelectQuery *>(select->table.get()) && !typeid_cast<const ASTFunction *>(select->table.get()))
 		{
 			String database = select->database
 				? typeid_cast<const ASTIdentifier &>(*select->database).name
@ -527,7 +528,7 @@ void ExpressionAnalyzer::normalizeTreeImpl(
 	/// rewrite правила, которые действуют при обходе сверху-вниз.
 	bool replaced = false;

-	ASTFunction * func_node = typeid_cast<ASTFunction *>(&*ast);
+	ASTFunction * func_node = typeid_cast<ASTFunction *>(ast.get());
 	if (func_node)
 	{
 		/** Нет ли в таблице столбца, название которого полностью совпадает с записью функции?
@ -545,7 +546,7 @@ void ExpressionAnalyzer::normalizeTreeImpl(

 		/// Может быть указано IN t, где t - таблица, что равносильно IN (SELECT * FROM t).
 		if (functionIsInOrGlobalInOperator(func_node->name))
-			if (ASTIdentifier * right = typeid_cast<ASTIdentifier *>(&*func_node->arguments->children.at(1)))
+			if (ASTIdentifier * right = typeid_cast<ASTIdentifier *>(func_node->arguments->children.at(1).get()))
 				right->kind = ASTIdentifier::Table;

 		/// А ещё, в качестве исключения, будем понимать count(*) как count(), а не count(список всех столбцов).
@ -555,7 +556,7 @@ void ExpressionAnalyzer::normalizeTreeImpl(
 			func_node->arguments->children.clear();
 		}
 	}
-	else if (ASTIdentifier * node = typeid_cast<ASTIdentifier *>(&*ast))
+	else if (ASTIdentifier * node = typeid_cast<ASTIdentifier *>(ast.get()))
 	{
 		if (node->kind == ASTIdentifier::Column)
 		{
@ -581,13 +582,13 @@ void ExpressionAnalyzer::normalizeTreeImpl(
 			}
 		}
 	}
-	else if (ASTExpressionList * node = typeid_cast<ASTExpressionList *>(&*ast))
+	else if (ASTExpressionList * node = typeid_cast<ASTExpressionList *>(ast.get()))
 	{
 		/// Заменим * на список столбцов.
 		ASTs & asts = node->children;
 		for (int i = static_cast<int>(asts.size()) - 1; i >= 0; --i)
 		{
-			if (ASTAsterisk * asterisk = typeid_cast<ASTAsterisk *>(&*asts[i]))
+			if (ASTAsterisk * asterisk = typeid_cast<ASTAsterisk *>(asts[i].get()))
 			{
 				ASTs all_columns;
 				for (const auto & column_name_type : columns)
@ -598,10 +599,10 @@ void ExpressionAnalyzer::normalizeTreeImpl(
 			}
 		}
 	}
-	else if (ASTJoin * node = typeid_cast<ASTJoin *>(&*ast))
+	else if (ASTJoin * node = typeid_cast<ASTJoin *>(ast.get()))
 	{
 		/// может быть указано JOIN t, где t - таблица, что равносильно JOIN (SELECT * FROM t).
-		if (ASTIdentifier * right = typeid_cast<ASTIdentifier *>(&*node->table))
+		if (ASTIdentifier * right = typeid_cast<ASTIdentifier *>(node->table.get()))
 			right->kind = ASTIdentifier::Table;
 	}

@ -626,7 +627,7 @@ void ExpressionAnalyzer::normalizeTreeImpl(
 		{
 			auto & child = func_node->arguments->children[i];

-			if (typeid_cast<ASTSelectQuery *>(&*child))
+			if (typeid_cast<const ASTSelectQuery *>(child.get()))
 				continue;

 			normalizeTreeImpl(child, finished_asts, current_asts, current_alias);
@ -636,7 +637,7 @@ void ExpressionAnalyzer::normalizeTreeImpl(
 	{
 		for (auto & child : ast->children)
 		{
-			if (typeid_cast<ASTSelectQuery *>(&*child))
+			if (typeid_cast<const ASTSelectQuery *>(child.get()))
 				continue;

 			normalizeTreeImpl(child, finished_asts, current_asts, current_alias);
@ -644,7 +645,7 @@ void ExpressionAnalyzer::normalizeTreeImpl(
 	}

 	/// Если секция WHERE или HAVING состоит из одного алиаса, ссылку нужно заменить не только в children, но и в where_expression и having_expression.
-	if (ASTSelectQuery * select = typeid_cast<ASTSelectQuery *>(&*ast))
+	if (ASTSelectQuery * select = typeid_cast<ASTSelectQuery *>(ast.get()))
 	{
 		if (select->prewhere_expression)
 			normalizeTreeImpl(select->prewhere_expression, finished_asts, current_asts, current_alias);
@ -656,7 +657,7 @@ void ExpressionAnalyzer::normalizeTreeImpl(

 	/// Действия, выполняемые снизу вверх.

-	if (ASTFunction * node = typeid_cast<ASTFunction *>(&*ast))
+	if (ASTFunction * node = typeid_cast<ASTFunction *>(ast.get()))
 	{
 		if (node->kind == ASTFunction::TABLE_FUNCTION)
 		{
@ -995,7 +996,7 @@ void ExpressionAnalyzer::makeSetsForIndexImpl(ASTPtr & node, const Block & sampl
 		IAST & args = *func->arguments;
 		ASTPtr & arg = args.children.at(1);

-		if (!typeid_cast<ASTSet *>(&*arg) && !typeid_cast<ASTSubquery *>(&*arg) && !typeid_cast<ASTIdentifier *>(&*arg))
+		if (!typeid_cast<ASTSet *>(arg.get()) && !typeid_cast<ASTSubquery *>(arg.get()) && !typeid_cast<ASTIdentifier *>(arg.get()))
 		{
 			try
 			{
@ -1016,8 +1017,8 @@ static SharedPtr<InterpreterSelectQuery> interpretSubquery(
 	ASTPtr & subquery_or_table_name, const Context & context, size_t subquery_depth, const Names & required_columns)
 {
 	/// Подзапрос или имя таблицы. Имя таблицы аналогично подзапросу SELECT * FROM t.
-	const ASTSubquery * subquery = typeid_cast<const ASTSubquery *>(&*subquery_or_table_name);
-	const ASTIdentifier * table = typeid_cast<const ASTIdentifier *>(&*subquery_or_table_name);
+	const ASTSubquery * subquery = typeid_cast<const ASTSubquery *>(subquery_or_table_name.get());
+	const ASTIdentifier * table = typeid_cast<const ASTIdentifier *>(subquery_or_table_name.get());

 	if (!subquery && !table)
 		throw Exception("IN/JOIN supports only SELECT subqueries.", ErrorCodes::BAD_ARGUMENTS);
@ -1119,12 +1120,12 @@ void ExpressionAnalyzer::makeSet(ASTFunction * node, const Block & sample_block)
 	ASTPtr & arg = args.children.at(1);

 	/// Уже преобразовали.
-	if (typeid_cast<ASTSet *>(&*arg))
+	if (typeid_cast<ASTSet *>(arg.get()))
 		return;

 	/// Если подзапрос или имя таблицы для SELECT.
-	ASTIdentifier * identifier = typeid_cast<ASTIdentifier *>(&*arg);
-	if (typeid_cast<ASTSubquery *>(&*arg) || identifier)
+	ASTIdentifier * identifier = typeid_cast<ASTIdentifier *>(arg.get());
+	if (typeid_cast<ASTSubquery *>(arg.get()) || identifier)
 	{
 		/// Получаем поток блоков для подзапроса. Создаём Set и кладём на место подзапроса.
 		String set_id = arg->getColumnName();
@ -1225,7 +1226,7 @@ void ExpressionAnalyzer::makeExplicitSet(ASTFunction * node, const Block & sampl
 	DataTypes set_element_types;
 	ASTPtr & left_arg = args.children.at(0);

-	ASTFunction * left_arg_tuple = typeid_cast<ASTFunction *>(&*left_arg);
+	ASTFunction * left_arg_tuple = typeid_cast<ASTFunction *>(left_arg.get());

 	if (left_arg_tuple && left_arg_tuple->name == "tuple")
 	{
@ -1243,7 +1244,7 @@ void ExpressionAnalyzer::makeExplicitSet(ASTFunction * node, const Block & sampl
 	else
 	{
 		DataTypePtr left_type = sample_block.getByName(left_arg->getColumnName()).type;
-		if (DataTypeArray * array_type = typeid_cast<DataTypeArray *>(&*left_type))
+		if (DataTypeArray * array_type = typeid_cast<DataTypeArray *>(left_type.get()))
 			set_element_types.push_back(array_type->getNestedType());
 		else
 			set_element_types.push_back(left_type);
@ -1253,7 +1254,7 @@ void ExpressionAnalyzer::makeExplicitSet(ASTFunction * node, const Block & sampl
 	bool single_value = false;
 	ASTPtr elements_ast = arg;

-	if (ASTFunction * set_func = typeid_cast<ASTFunction *>(&*arg))
+	if (ASTFunction * set_func = typeid_cast<ASTFunction *>(arg.get()))
 	{
 		if (set_func->name == "tuple")
 		{
@ -1264,8 +1265,8 @@ void ExpressionAnalyzer::makeExplicitSet(ASTFunction * node, const Block & sampl
 			}
 			else
 			{
-				/// Отличм случай (x, y) in ((1, 2), (3, 4)) от случая (x, y) in (1, 2).
-				ASTFunction * any_element = typeid_cast<ASTFunction *>(&*set_func->arguments->children.at(0));
+				/// Отличим случай (x, y) in ((1, 2), (3, 4)) от случая (x, y) in (1, 2).
+				ASTFunction * any_element = typeid_cast<ASTFunction *>(set_func->arguments->children.at(0).get());
 				if (set_element_types.size() >= 2 && (!any_element || any_element->name != "tuple"))
 					single_value = true;
 				else
@ -1282,7 +1283,7 @@ void ExpressionAnalyzer::makeExplicitSet(ASTFunction * node, const Block & sampl
 			single_value = true;
 		}
 	}
-	else if (typeid_cast<ASTLiteral *>(&*arg))
+	else if (typeid_cast<ASTLiteral *>(arg.get()))
 	{
 		single_value = true;
 	}
@ -1436,7 +1437,7 @@ void ExpressionAnalyzer::getArrayJoinedColumns()
 			const String nested_table_name = ast->getColumnName();
 			const String nested_table_alias = ast->getAliasOrColumnName();

-			if (nested_table_alias == nested_table_name && !typeid_cast<const ASTIdentifier *>(&*ast))
+			if (nested_table_alias == nested_table_name && !typeid_cast<const ASTIdentifier *>(ast.get()))
 				throw Exception("No alias for non-trivial value in ARRAY JOIN: " + nested_table_name, ErrorCodes::ALIAS_REQUIRED);

 			if (array_join_alias_to_name.count(nested_table_alias) || aliases.count(nested_table_alias))
@ -1466,7 +1467,7 @@ void ExpressionAnalyzer::getArrayJoinedColumns()
 			String result_name = expr->getAliasOrColumnName();

 			/// Это массив.
-			if (!typeid_cast<ASTIdentifier *>(&*expr) || findColumn(source_name, columns) != columns.end())
+			if (!typeid_cast<ASTIdentifier *>(expr.get()) || findColumn(source_name, columns) != columns.end())
 			{
 				array_join_result_to_source[result_name] = source_name;
 			}
@ -1495,7 +1496,7 @@ void ExpressionAnalyzer::getArrayJoinedColumns()
 /// Заполняет array_join_result_to_source: по каким столбцам-массивам размножить, и как их после этого назвать.
 void ExpressionAnalyzer::getArrayJoinedColumnsImpl(ASTPtr ast)
 {
-	if (ASTIdentifier * node = typeid_cast<ASTIdentifier *>(&*ast))
+	if (ASTIdentifier * node = typeid_cast<ASTIdentifier *>(ast.get()))
 	{
 		if (node->kind == ASTIdentifier::Column)
 		{
@ -1528,7 +1529,7 @@ void ExpressionAnalyzer::getArrayJoinedColumnsImpl(ASTPtr ast)
 	else
 	{
 		for (auto & child : ast->children)
-			if (!typeid_cast<const ASTSelectQuery *>(&*child))
+			if (!typeid_cast<const ASTSelectQuery *>(child.get()))
 				getArrayJoinedColumnsImpl(child);
 	}
 }
@ -1537,11 +1538,11 @@ void ExpressionAnalyzer::getArrayJoinedColumnsImpl(ASTPtr ast)
 void ExpressionAnalyzer::getActionsImpl(ASTPtr ast, bool no_subqueries, bool only_consts, ScopeStack & actions_stack)
 {
 	/// Если результат вычисления уже есть в блоке.
-	if ((typeid_cast<ASTFunction *>(&*ast) || typeid_cast<ASTLiteral *>(&*ast))
+	if ((typeid_cast<ASTFunction *>(ast.get()) || typeid_cast<ASTLiteral *>(ast.get()))
 		&& actions_stack.getSampleBlock().has(ast->getColumnName()))
 		return;

-	if (ASTIdentifier * node = typeid_cast<ASTIdentifier *>(&*ast))
+	if (ASTIdentifier * node = typeid_cast<ASTIdentifier *>(ast.get()))
 	{
 		std::string name = node->getColumnName();
 		if (!only_consts && !actions_stack.getSampleBlock().has(name))
@ -1559,10 +1560,10 @@ void ExpressionAnalyzer::getActionsImpl(ASTPtr ast, bool no_subqueries, bool onl
 					ErrorCodes::NOT_AN_AGGREGATE);
 		}
 	}
-	else if (ASTFunction * node = typeid_cast<ASTFunction *>(&*ast))
+	else if (ASTFunction * node = typeid_cast<ASTFunction *>(ast.get()))
 	{
 		if (node->kind == ASTFunction::LAMBDA_EXPRESSION)
-			throw Exception("Unexpected expression", ErrorCodes::UNEXPECTED_EXPRESSION);
+			throw Exception("Unexpected lambda expression", ErrorCodes::UNEXPECTED_EXPRESSION);

 		/// Функция arrayJoin.
 		if (node->kind == ASTFunction::ARRAY_JOIN)
@ -1623,15 +1624,15 @@ void ExpressionAnalyzer::getActionsImpl(ASTPtr ast, bool no_subqueries, bool onl

 			for (auto & child : node->arguments->children)
 			{
-				ASTFunction * lambda = typeid_cast<ASTFunction *>(&*child);
-				ASTSet * set = typeid_cast<ASTSet *>(&*child);
+				ASTFunction * lambda = typeid_cast<ASTFunction *>(child.get());
+				ASTSet * set = typeid_cast<ASTSet *>(child.get());
 				if (lambda && lambda->name == "lambda")
 				{
 					/// Если аргумент - лямбда-выражение, только запомним его примерный тип.
 					if (lambda->arguments->children.size() != 2)
 						throw Exception("lambda requires two arguments", ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);

-					ASTFunction * lambda_args_tuple = typeid_cast<ASTFunction *>(&*lambda->arguments->children.at(0));
+					ASTFunction * lambda_args_tuple = typeid_cast<ASTFunction *>(lambda->arguments->children.at(0).get());

 					if (!lambda_args_tuple || lambda_args_tuple->name != "tuple")
 						throw Exception("First argument of lambda must be a tuple", ErrorCodes::TYPE_MISMATCH);
@ -1701,17 +1702,17 @@ void ExpressionAnalyzer::getActionsImpl(ASTPtr ast, bool no_subqueries, bool onl
 				{
 					ASTPtr child = node->arguments->children[i];

-					ASTFunction * lambda = typeid_cast<ASTFunction *>(&*child);
+					ASTFunction * lambda = typeid_cast<ASTFunction *>(child.get());
 					if (lambda && lambda->name == "lambda")
 					{
-						DataTypeExpression * lambda_type = typeid_cast<DataTypeExpression *>(&*argument_types[i]);
-						ASTFunction * lambda_args_tuple = typeid_cast<ASTFunction *>(&*lambda->arguments->children.at(0));
+						DataTypeExpression * lambda_type = typeid_cast<DataTypeExpression *>(argument_types[i].get());
+						ASTFunction * lambda_args_tuple = typeid_cast<ASTFunction *>(lambda->arguments->children.at(0).get());
 						ASTs lambda_arg_asts = lambda_args_tuple->arguments->children;
 						NamesAndTypesList lambda_arguments;

 						for (size_t j = 0; j < lambda_arg_asts.size(); ++j)
 						{
-							ASTIdentifier * identifier = typeid_cast<ASTIdentifier *>(&*lambda_arg_asts[j]);
+							ASTIdentifier * identifier = typeid_cast<ASTIdentifier *>(lambda_arg_asts[j].get());
 							if (!identifier)
 								throw Exception("lambda argument declarations must be identifiers", ErrorCodes::TYPE_MISMATCH);

@ -1764,7 +1765,7 @@ void ExpressionAnalyzer::getActionsImpl(ASTPtr ast, bool no_subqueries, bool onl
 										additional_requirements);
 		}
 	}
-	else if (ASTLiteral * node = typeid_cast<ASTLiteral *>(&*ast))
+	else if (ASTLiteral * node = typeid_cast<ASTLiteral *>(ast.get()))
 	{
 		DataTypePtr type = apply_visitor(FieldToDataType(), node->value);

@ -1783,9 +1784,23 @@ void ExpressionAnalyzer::getActionsImpl(ASTPtr ast, bool no_subqueries, bool onl
 }


-void ExpressionAnalyzer::getAggregates(ASTPtr ast, ExpressionActionsPtr & actions)
+void ExpressionAnalyzer::getAggregates(const ASTPtr & ast, ExpressionActionsPtr & actions)
 {
-	ASTFunction * node = typeid_cast<ASTFunction *>(&*ast);
+	/// Внутри WHERE и PREWHERE не может быть агрегатных функций.
+	if (select_query && (ast.get() == select_query->where_expression.get() || ast.get() == select_query->prewhere_expression.get()))
+	{
+		assertNoAggregates(ast, "in WHERE or PREWHERE");
+		return;
+	}
+
+	/// Если мы анализируем не запрос SELECT, а отдельное выражение, то в нём не может быть агрегатных функций.
+	if (!select_query)
+	{
+		assertNoAggregates(ast, "in wrong place");
+		return;
+	}
+
+	const ASTFunction * node = typeid_cast<const ASTFunction *>(ast.get());
 	if (node && node->kind == ASTFunction::AGGREGATE_FUNCTION)
 	{
 		has_aggregation = true;
@ -1797,12 +1812,15 @@ void ExpressionAnalyzer::getAggregates(ASTPtr ast, ExpressionActionsPtr & action
 			if (aggregate_descriptions[i].column_name == aggregate.column_name)
 				return;

-		ASTs & arguments = node->arguments->children;
+		const ASTs & arguments = node->arguments->children;
 		aggregate.argument_names.resize(arguments.size());
 		DataTypes types(arguments.size());

 		for (size_t i = 0; i < arguments.size(); ++i)
 		{
+			/// Внутри агрегатных функций не может быть других агрегатных функций.
+			assertNoAggregates(arguments[i], "inside another aggregate function");
+
 			getRootActions(arguments[i], true, false, actions);
 			const std::string & name = arguments[i]->getColumnName();
 			types[i] = actions->getSampleBlock().getByName(name).type;
@ -1813,14 +1831,15 @@ void ExpressionAnalyzer::getAggregates(ASTPtr ast, ExpressionActionsPtr & action

 		if (node->parameters)
 		{
-			ASTs & parameters = typeid_cast<ASTExpressionList &>(*node->parameters).children;
+			const ASTs & parameters = typeid_cast<const ASTExpressionList &>(*node->parameters).children;
 			Array params_row(parameters.size());

 			for (size_t i = 0; i < parameters.size(); ++i)
 			{
-				ASTLiteral * lit = typeid_cast<ASTLiteral *>(&*parameters[i]);
+				const ASTLiteral * lit = typeid_cast<const ASTLiteral *>(parameters[i].get());
 				if (!lit)
-					throw Exception("Parameters to aggregate functions must be literals", ErrorCodes::PARAMETERS_TO_AGGREGATE_FUNCTIONS_MUST_BE_LITERALS);
+					throw Exception("Parameters to aggregate functions must be literals",
+						ErrorCodes::PARAMETERS_TO_AGGREGATE_FUNCTIONS_MUST_BE_LITERALS);

 				params_row[i] = lit->value;
 			}
@ -1835,15 +1854,27 @@ void ExpressionAnalyzer::getAggregates(ASTPtr ast, ExpressionActionsPtr & action
 	}
 	else
 	{
-		for (size_t i = 0; i < ast->children.size(); ++i)
-		{
-			ASTPtr child = ast->children[i];
-			if (!typeid_cast<ASTSubquery *>(&*child) && !typeid_cast<ASTSelectQuery *>(&*child))
+		for (const auto & child : ast->children)
+			if (!typeid_cast<const ASTSubquery *>(child.get()) && !typeid_cast<const ASTSelectQuery *>(child.get()))
 				getAggregates(child, actions);
-		}
 	}
 }

+
+void ExpressionAnalyzer::assertNoAggregates(const ASTPtr & ast, const char * description)
+{
+	const ASTFunction * node = typeid_cast<const ASTFunction *>(ast.get());
+
+	if (node && node->kind == ASTFunction::AGGREGATE_FUNCTION)
+		throw Exception("Aggregate function " + node->getColumnName()
+			+ " is found " + String(description) + " in query", ErrorCodes::ILLEGAL_AGGREGATION);
+
+	for (const auto & child : ast->children)
+		if (!typeid_cast<const ASTSubquery *>(child.get()) && !typeid_cast<const ASTSelectQuery *>(child.get()))
+			assertNoAggregates(child, description);
+}
+
+
 void ExpressionAnalyzer::assertSelect() const
 {
 	if (!select_query)
@ -1930,7 +1961,7 @@ bool ExpressionAnalyzer::appendJoin(ExpressionActionsChain & chain, bool only_ty

 	/// Особый случай - если справа JOIN указано имя таблицы, при чём, таблица имеет тип Join (заранее подготовленное отображение).
 	/// TODO В этом синтаксисе не поддерживается указание имени БД.
-	ASTIdentifier * identifier = typeid_cast<ASTIdentifier *>(&*ast_join.table);
+	ASTIdentifier * identifier = typeid_cast<ASTIdentifier *>(ast_join.table.get());
 	if (identifier)
 	{
 		StoragePtr table = context.tryGetTable("", identifier->name);
@ -2087,7 +2118,7 @@ bool ExpressionAnalyzer::appendOrderBy(ExpressionActionsChain & chain, bool only
 	ASTs asts = select_query->order_expression_list->children;
 	for (size_t i = 0; i < asts.size(); ++i)
 	{
-		ASTOrderByElement * ast = typeid_cast<ASTOrderByElement *>(&*asts[i]);
+		ASTOrderByElement * ast = typeid_cast<ASTOrderByElement *>(asts[i].get());
 		if (!ast || ast->children.size() != 1)
 			throw Exception("Bad order expression AST", ErrorCodes::UNKNOWN_TYPE_OF_AST_NODE);
 		ASTPtr order_expression = ast->children.at(0);
@ -2138,7 +2169,7 @@ Block ExpressionAnalyzer::getSelectSampleBlock()

 void ExpressionAnalyzer::getActionsBeforeAggregation(ASTPtr ast, ExpressionActionsPtr & actions, bool no_subqueries)
 {
-	ASTFunction * node = typeid_cast<ASTFunction *>(&*ast);
+	ASTFunction * node = typeid_cast<ASTFunction *>(ast.get());

 	if (node && node->kind == ASTFunction::AGGREGATE_FUNCTION)
 		for (auto & argument : node->arguments->children)
@ -2157,7 +2188,7 @@ ExpressionActionsPtr ExpressionAnalyzer::getActions(bool project_result)

 	ASTs asts;

-	if (auto node = typeid_cast<const ASTExpressionList *>(&*ast))
+	if (auto node = typeid_cast<const ASTExpressionList *>(ast.get()))
 		asts = node->children;
 	else
 		asts = ASTs(1, ast);
@ -2226,7 +2257,7 @@ void ExpressionAnalyzer::collectUsedColumns()
 		{
 			/// Игнорируем идентификаторы верхнего уровня из секции ARRAY JOIN.
 			/// Их потом добавим отдельно.
-			if (typeid_cast<ASTIdentifier *>(&*expressions[i]))
+			if (typeid_cast<ASTIdentifier *>(expressions[i].get()))
 			{
 				ignored.insert(expressions[i]->getColumnName());
 			}
@ -2389,7 +2420,7 @@ void ExpressionAnalyzer::getRequiredColumnsImpl(ASTPtr ast,
 	  * - идентификаторы, доступные из JOIN-а, кладём в required_joined_columns.
 	  */

-	if (ASTIdentifier * node = typeid_cast<ASTIdentifier *>(&*ast))
+	if (ASTIdentifier * node = typeid_cast<ASTIdentifier *>(ast.get()))
 	{
 		if (node->kind == ASTIdentifier::Column
 			&& !ignored_names.count(node->name)
@ -2404,14 +2435,14 @@ void ExpressionAnalyzer::getRequiredColumnsImpl(ASTPtr ast,
 		return;
 	}

-	if (ASTFunction * node = typeid_cast<ASTFunction *>(&*ast))
+	if (ASTFunction * node = typeid_cast<ASTFunction *>(ast.get()))
 	{
 		if (node->kind == ASTFunction::LAMBDA_EXPRESSION)
 		{
 			if (node->arguments->children.size() != 2)
 				throw Exception("lambda requires two arguments", ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);

-			ASTFunction * lambda_args_tuple = typeid_cast<ASTFunction *>(&*node->arguments->children.at(0));
+			ASTFunction * lambda_args_tuple = typeid_cast<ASTFunction *>(node->arguments->children.at(0).get());

 			if (!lambda_args_tuple || lambda_args_tuple->name != "tuple")
 				throw Exception("First argument of lambda must be a tuple", ErrorCodes::TYPE_MISMATCH);
@ -2420,7 +2451,7 @@ void ExpressionAnalyzer::getRequiredColumnsImpl(ASTPtr ast,
 			Names added_ignored;
 			for (auto & child : lambda_args_tuple->arguments->children)
 			{
-				ASTIdentifier * identifier = typeid_cast<ASTIdentifier *>(&*child);
+				ASTIdentifier * identifier = typeid_cast<ASTIdentifier *>(child.get());
 				if (!identifier)
 					throw Exception("lambda argument declarations must be identifiers", ErrorCodes::TYPE_MISMATCH);

@ -2443,7 +2474,7 @@ void ExpressionAnalyzer::getRequiredColumnsImpl(ASTPtr ast,
 		}
 	}

-	ASTSelectQuery * select = typeid_cast<ASTSelectQuery *>(&*ast);
+	ASTSelectQuery * select = typeid_cast<ASTSelectQuery *>(ast.get());

 	/// Рекурсивный обход выражения.
 	for (auto & child : ast->children)
@ -2451,7 +2482,7 @@ void ExpressionAnalyzer::getRequiredColumnsImpl(ASTPtr ast,
 		/** Не пойдем в секцию ARRAY JOIN, потому что там нужно смотреть на имена не-ARRAY-JOIN-енных столбцов.
 		  * Туда collectUsedColumns отправит нас отдельно.
 		  */
-		if (!typeid_cast<ASTSubquery *>(&*child) && !typeid_cast<ASTSelectQuery *>(&*child) &&
+		if (!typeid_cast<ASTSubquery *>(child.get()) && !typeid_cast<ASTSelectQuery *>(child.get()) &&
 			!(select && child == select->array_join_expression_list))
 			getRequiredColumnsImpl(child, required_columns, ignored_names, available_joined_columns, required_joined_columns);
    }
--- a/dbms/src/Interpreters/InterpreterCreateQuery.cpp
+++ b/dbms/src/Interpreters/InterpreterCreateQuery.cpp
@ -163,11 +163,12 @@ BlockIO InterpreterCreateQuery::executeImpl(bool assume_metadata_exists)
 		create.children.push_back(new_columns);
 	create.columns = new_columns;

-	auto ast_element_for_engine = [](const char * engine)
+	auto set_engine = [&](const char * engine)
 	{
+		storage_name = engine;
 		ASTFunction * func = new ASTFunction();
 		func->name = engine;
-		return func;
+		create.storage = func;
 	};

 	/// Выбор нужного движка таблицы
@ -182,11 +183,11 @@ BlockIO InterpreterCreateQuery::executeImpl(bool assume_metadata_exists)
 		create.storage = typeid_cast<const ASTCreateQuery &>(*context.getCreateQuery(as_database_name, as_table_name)).storage;
 	}
 	else if (create.is_temporary)
-		create.storage = ast_element_for_engine("Memory");
+		set_engine("Memory");
 	else if (create.is_view)
-		create.storage = ast_element_for_engine("View");
+		set_engine("View");
 	else if (create.is_materialized_view)
-		create.storage = ast_element_for_engine("MaterializedView");
+		set_engine("MaterializedView");
 	else
 		throw Exception("Incorrect CREATE query: required ENGINE.", ErrorCodes::ENGINE_REQUIRED);

--- a/dbms/src/Parsers/ParserSelectQuery.cpp
+++ b/dbms/src/Parsers/ParserSelectQuery.cpp
@ -1,3 +1,4 @@
+#include <memory>
 #include <DB/Parsers/ASTSelectQuery.h>
 #include <DB/Parsers/ASTIdentifier.h>
 #include <DB/Parsers/IParserBase.h>
@ -8,10 +9,16 @@
 #include <DB/Parsers/ParserSetQuery.h>
 #include <DB/Parsers/ParserSampleRatio.h>
 #include <DB/Parsers/ParserSelectQuery.h>
+#include <DB/Parsers/ParserTableExpression.h>

 namespace DB
 {

+namespace ErrorCodes
+{
+	extern const int SYNTAX_ERROR;
+}
+

 bool ParserSelectQuery::parseImpl(Pos & pos, Pos end, ASTPtr & node, Pos & max_parsed_pos, Expected & expected)
 {
@ -75,65 +82,27 @@ bool ParserSelectQuery::parseImpl(Pos & pos, Pos end, ASTPtr & node, Pos & max_p
 	{
 		ws.ignore(pos, end);

-		ParserString s_lparen("(");
-		ParserString s_rparen(")");
-		ParserString s_dot(".");
-		ParserIdentifier ident;
-		ParserFunction table_function;
-		Pos before = pos;
+		ParserWithOptionalAlias table_p(std::make_unique<ParserTableExpression>(), true);
+		if (!table_p.parse(pos, end, select_query->table, max_parsed_pos, expected))
+			return false;

-		if (s_lparen.ignore(pos, end, max_parsed_pos, expected))
+		/// Раскрываем составной идентификатор в имя БД и имя таблицы. NOTE Можно избавиться от этого в будущем.
+		if (const ASTIdentifier * table_identifier = typeid_cast<const ASTIdentifier *>(select_query->table.get()))
 		{
-			ws.ignore(pos, end);
+			if (table_identifier->children.size() > 2)
+				throw Exception("Too many components to table. Table may be specified either in database.table or in table form",
+					ErrorCodes::SYNTAX_ERROR);

-			ParserSelectQuery select_p;
-			if (!select_p.parse(pos, end, select_query->table, max_parsed_pos, expected))
-				return false;
-
-			ws.ignore(pos, end);
-
-			if (!s_rparen.ignore(pos, end, max_parsed_pos, expected))
-				return false;
-
-			ws.ignore(pos, end);
-		}
-		else if (ident.parse(pos, end, select_query->table, max_parsed_pos, expected))
-		{
-			/// Если сразу после identifier идет скобка, значит это должна быть табличная функция
-			if (s_lparen.ignore(pos, end, max_parsed_pos, expected))
+			if (table_identifier->children.size() == 2)
 			{
-				pos = before;
-				if (!table_function.parse(pos, end, select_query->table, max_parsed_pos, expected))
-					return false;
-				if (select_query->table)
-					typeid_cast<ASTFunction &>(*select_query->table).kind = ASTFunction::TABLE_FUNCTION;
-				ws.ignore(pos, end);
-			}
-			else
-			{
-				ws.ignore(pos, end);
-				if (s_dot.ignore(pos, end, max_parsed_pos, expected))
-				{
-					select_query->database = select_query->table;
+				select_query->database = table_identifier->children.at(0);
+				typeid_cast<ASTIdentifier &>(*select_query->database).kind = ASTIdentifier::Database;

-					ws.ignore(pos, end);
-
-					if (!ident.parse(pos, end, select_query->table, max_parsed_pos, expected))
-						return false;
-
-					ws.ignore(pos, end);
-				}
-
-				if (select_query->database)
-					typeid_cast<ASTIdentifier &>(*select_query->database).kind = ASTIdentifier::Database;
+				select_query->table = table_identifier->children.at(1);
 				typeid_cast<ASTIdentifier &>(*select_query->table).kind = ASTIdentifier::Table;
 			}
 		}
-		else
-			return false;

-		/// Может быть указан алиас. На данный момент, он ничего не значит и не используется.
-		ParserAlias(true).ignore(pos, end);
 		ws.ignore(pos, end);
 	}

--- a/dbms/src/Parsers/ParserTableExpression.cpp
+++ b/dbms/src/Parsers/ParserTableExpression.cpp
@ -0,0 +1,63 @@
+#include <DB/Parsers/CommonParsers.h>
+#include <DB/Parsers/ExpressionElementParsers.h>
+#include <DB/Parsers/ExpressionListParsers.h>
+#include <DB/Parsers/ASTFunction.h>
+#include <DB/Parsers/ASTIdentifier.h>
+#include <DB/Parsers/ParserSelectQuery.h>
+#include <DB/Parsers/ParserTableExpression.h>
+
+
+namespace DB
+{
+
+
+bool ParserTableExpression::parseImpl(Pos & pos, Pos end, ASTPtr & node, Pos & max_parsed_pos, Expected & expected)
+{
+	ParserWhiteSpaceOrComments ws;
+	ParserString s_lparen("(");
+	ParserString s_rparen(")");
+	ParserCompoundIdentifier ident;
+	ParserFunction table_function;
+	Pos before = pos;
+
+	if (s_lparen.ignore(pos, end, max_parsed_pos, expected))
+	{
+		/// Подзапрос.
+		ws.ignore(pos, end);
+
+		ParserSelectQuery select_p;
+		if (!select_p.parse(pos, end, node, max_parsed_pos, expected))
+			return false;
+
+		ws.ignore(pos, end);
+
+		if (!s_rparen.ignore(pos, end, max_parsed_pos, expected))
+			return false;
+
+		ws.ignore(pos, end);
+	}
+	else if (ident.parse(pos, end, node, max_parsed_pos, expected))
+	{
+		/// Если сразу после identifier идет скобка, значит это должна быть табличная функция
+		if (s_lparen.ignore(pos, end, max_parsed_pos, expected))
+		{
+			pos = before;
+			if (!table_function.parse(pos, end, node, max_parsed_pos, expected))
+				return false;
+			if (node)
+				typeid_cast<ASTFunction &>(*node).kind = ASTFunction::TABLE_FUNCTION;
+			ws.ignore(pos, end);
+		}
+		else
+		{
+			ws.ignore(pos, end);
+			typeid_cast<ASTIdentifier &>(*node).kind = ASTIdentifier::Table;
+		}
+	}
+	else
+		return false;
+
+	return true;
+}
+
+}
--- a/dbms/src/Server/clickhouse-server.logrt
+++ b/dbms/src/Server/clickhouse-server.logrt
@ -1,6 +1,6 @@
 /var/log/clickhouse-server/clickhouse-server*.log {
-	rotate 20
-	size 20M
+	rotate 100
+	size 100M
 	compress
 	missingok
 	sharedscripts
--- a/dbms/src/Server/data/default/hits/.gitignore
+++ b/dbms/src/Server/data/default/hits/.gitignore
--- a/dbms/src/Server/metadata/default/hits.sql
+++ b/dbms/src/Server/metadata/default/hits.sql
@ -1,62 +0,0 @@
-ATTACH TABLE hits
-(
-    WatchID UInt64
-,     JavaEnable UInt8
-,     Title String
-,     GoodEvent UInt32
-,     EventTime DateTime
-,     CounterID UInt32
-,     ClientIP UInt32
-,     RegionID UInt32
-,     UniqID UInt64
-,     CounterClass UInt8
-,     OS UInt8
-,     UserAgent UInt8
-,     URL String
-,     Referer String
-,     Refresh UInt8
-,     ResolutionWidth UInt16
-,     ResolutionHeight UInt16
-,     ResolutionDepth UInt8
-,     FlashMajor UInt8
-,     FlashMinor UInt8
-,     FlashMinor2 String
-,     NetMajor UInt8
-,     NetMinor UInt8
-,     UserAgentMajor UInt16
-,     UserAgentMinor FixedString(2)
-,     CookieEnable UInt8
-,     JavascriptEnable UInt8
-,     IsMobile UInt8
-,     IsTablet UInt8
-,     MobilePhone UInt8
-,     MobilePhoneModel String
-,     Params String
-,     IPNetworkID UInt32
-,     TraficSourceID Int8
-,     SearchEngineID UInt16
-,     SearchPhrase String
-,     AdvEngineID UInt8
-,     IsArtifical UInt8
-,     WindowClientWidth UInt16
-,     WindowClientHeight UInt16
-,     ClientTimeZone Int16
-,     ClientEventTime DateTime
-,     SilverlightVersion1 UInt8
-,     SilverlightVersion2 UInt8
-,     SilverlightVersion3 UInt32
-,     SilverlightVersion4 UInt16
-,     PageCharset String
-,     CodeVersion UInt32
-,     IsLink UInt8
-,     IsDownload UInt8
-,     IsNotBounce UInt8
-,     FUniqID UInt64
-,     OriginalURL String
-,     HID UInt32
-,     IsOldCounter UInt8
-,     IsEvent UInt8
-,     IsParameter UInt8
-,     DontCountHits UInt8
-,     WithHash UInt8
-) ENGINE = Log
--- a/dbms/src/Storages/MergeTree/MergeTreeDataSelectExecutor.cpp
+++ b/dbms/src/Storages/MergeTree/MergeTreeDataSelectExecutor.cpp
@ -26,6 +26,7 @@ namespace DB
 namespace ErrorCodes
 {
 	extern const int INDEX_NOT_USED;
+	extern const int SAMPLING_NOT_SUPPORTED;
 }


@ -36,7 +37,7 @@ MergeTreeDataSelectExecutor::MergeTreeDataSelectExecutor(MergeTreeData & data_)


 /// Построить блок состоящий только из возможных значений виртуальных столбцов
-static Block getBlockWithVirtualColumns(const MergeTreeData::DataPartsVector & parts)
+static Block getBlockWithPartColumn(const MergeTreeData::DataPartsVector & parts)
 {
 	Block res;
 	ColumnWithTypeAndName _part(new ColumnString, new DataTypeString, "_part");
@ -105,41 +106,69 @@ BlockInputStreams MergeTreeDataSelectExecutor::read(
 	QueryProcessingStage::Enum & processed_stage,
 	const size_t max_block_size,
 	const unsigned threads,
-	size_t * part_index,
+	size_t * inout_part_index,
 	Int64 max_block_number_to_read) const
 {
 	size_t part_index_var = 0;
-	if (!part_index)
-		part_index = &part_index_var;
+	if (!inout_part_index)
+		inout_part_index = &part_index_var;

 	MergeTreeData::DataPartsVector parts = data.getDataPartsVector();

-	/// Если в запросе есть ограничения на виртуальный столбец _part, выберем только подходящие под него куски.
-	Names virt_column_names, real_column_names;
+	/// Если в запросе есть ограничения на виртуальный столбец _part или _part_index, выберем только подходящие под него куски.
+	/// В запросе может быть запрошен виртуальный столбец _sample_factor - 1 / использованный коэффициент сэмплирования.
+	Names virt_column_names;
+	Names real_column_names;
+
+	bool part_column_queried = false;
+
+	bool sample_factor_column_queried = false;
+	Float64 used_sample_factor = 1;
+
 	for (const String & name : column_names_to_return)
-		if (name != "_part" &&
-			name != "_part_index")
-			real_column_names.push_back(name);
-		else
+	{
+		if (name == "_part")
+		{
+			part_column_queried = true;
 			virt_column_names.push_back(name);
+		}
+		else if (name == "_part_index")
+		{
+			virt_column_names.push_back(name);
+		}
+		else if (name == "_sample_factor")
+		{
+			sample_factor_column_queried = true;
+			virt_column_names.push_back(name);
+		}
+		else
+		{
+			real_column_names.push_back(name);
+		}
+	}
+
+	NamesAndTypesList available_real_columns = data.getColumnsList();
+
+	NamesAndTypesList available_real_and_virtual_columns = available_real_columns;
+	for (const auto & name : virt_column_names)
+		available_real_and_virtual_columns.emplace_back(data.getColumn(name));

 	/// Если в запросе только виртуальные столбцы, надо запросить хотя бы один любой другой.
 	if (real_column_names.empty())
-		real_column_names.push_back(ExpressionActions::getSmallestColumn(data.getColumnsList()));
+		real_column_names.push_back(ExpressionActions::getSmallestColumn(available_real_columns));

-	Block virtual_columns_block = getBlockWithVirtualColumns(parts);
-
-	/// Если запрошен хотя бы один виртуальный столбец, пробуем индексировать
-	if (!virt_column_names.empty())
+	/// Если запрошен виртуальный столбец _part, пробуем использовать его в качестве индекса.
+	Block virtual_columns_block = getBlockWithPartColumn(parts);
+	if (part_column_queried)
 		VirtualColumnUtils::filterBlockWithQuery(query, virtual_columns_block, context);

-	std::multiset<String> values = VirtualColumnUtils::extractSingleValueFromBlock<String>(virtual_columns_block, "_part");
+	std::multiset<String> part_values = VirtualColumnUtils::extractSingleValueFromBlock<String>(virtual_columns_block, "_part");

 	data.check(real_column_names);
 	processed_stage = QueryProcessingStage::FetchColumns;

-	PKCondition key_condition(query, context, data.getColumnsList(), data.getSortDescription());
-	PKCondition date_condition(query, context, data.getColumnsList(), SortDescription(1, SortColumnDescription(data.date_column_name, 1)));
+	PKCondition key_condition(query, context, available_real_and_virtual_columns, data.getSortDescription());
+	PKCondition date_condition(query, context, available_real_and_virtual_columns, SortDescription(1, SortColumnDescription(data.date_column_name, 1)));

 	if (settings.force_primary_key && key_condition.alwaysUnknownOrTrue())
 		throw Exception("Primary key is not used and setting 'force_primary_key' is set.", ErrorCodes::INDEX_NOT_USED);
@ -157,7 +186,7 @@ BlockInputStreams MergeTreeDataSelectExecutor::read(

 		for (const auto & part : prev_parts)
 		{
-			if (values.find(part->name) == values.end())
+			if (part_values.find(part->name) == part_values.end())
 				continue;

 			Field left = static_cast<UInt64>(part->left_date);
@ -265,6 +294,12 @@ BlockInputStreams MergeTreeDataSelectExecutor::read(

 	if (use_sampling)
 	{
+		if (!data.sampling_expression)
+			throw Exception("Illegal SAMPLE: table doesn't support sampling", ErrorCodes::SAMPLING_NOT_SUPPORTED);
+
+		if (sample_factor_column_queried && relative_sample_size != 0)
+			used_sample_factor = 1.0 / boost::rational_cast<Float64>(relative_sample_size);
+
 		RelativeSize size_of_universum = 0;
 		DataTypePtr type = data.getPrimaryExpression()->getSampleBlock().getByName(data.sampling_expression->getColumnName()).type;

@ -277,7 +312,8 @@ BlockInputStreams MergeTreeDataSelectExecutor::read(
 		else if (typeid_cast<const DataTypeUInt8 *>(type.get()))
 			size_of_universum = RelativeSize(std::numeric_limits<UInt8>::max()) + 1;
 		else
-			throw Exception("Invalid sampling column type in storage parameters: " + type->getName() + ". Must be unsigned integer type.", ErrorCodes::ILLEGAL_TYPE_OF_COLUMN_FOR_FILTER);
+			throw Exception("Invalid sampling column type in storage parameters: " + type->getName() + ". Must be unsigned integer type.",
+				ErrorCodes::ILLEGAL_TYPE_OF_COLUMN_FOR_FILTER);

 		if (settings.parallel_replicas_count > 1)
 		{
@ -376,7 +412,7 @@ BlockInputStreams MergeTreeDataSelectExecutor::read(
 				filter_function->children.push_back(filter_function->arguments);
 			}

-			filter_expression = ExpressionAnalyzer(filter_function, context, nullptr, data.getColumnsList()).getActions(false);
+			filter_expression = ExpressionAnalyzer(filter_function, context, nullptr, available_real_columns).getActions(false);

 			/// Добавим столбцы, нужные для sampling_expression.
 			std::vector<String> add_columns = filter_expression->getRequiredColumns();
@ -400,7 +436,7 @@ BlockInputStreams MergeTreeDataSelectExecutor::read(
 	String prewhere_column;
 	if (select.prewhere_expression)
 	{
-		ExpressionAnalyzer analyzer(select.prewhere_expression, context, nullptr, data.getColumnsList());
+		ExpressionAnalyzer analyzer(select.prewhere_expression, context, nullptr, available_real_columns);
 		prewhere_actions = analyzer.getActions(false);
 		prewhere_column = select.prewhere_expression->getColumnName();
 		SubqueriesForSets prewhere_subqueries = analyzer.getSubqueriesForSets();
@ -420,7 +456,7 @@ BlockInputStreams MergeTreeDataSelectExecutor::read(
 	size_t sum_ranges = 0;
 	for (auto & part : parts)
 	{
-		RangesInDataPart ranges(part, (*part_index)++);
+		RangesInDataPart ranges(part, (*inout_part_index)++);

 		if (data.mode != MergeTreeData::Unsorted)
 			ranges.ranges = markRangesFromPKRange(part->index, key_condition, settings);
@ -487,6 +523,12 @@ BlockInputStreams MergeTreeDataSelectExecutor::read(
 		for (auto & stream : res)
 			stream = new FilterBlockInputStream(stream, filter_expression, filter_function->getColumnName());

+	/// Кстати, если делается распределённый запрос или запрос к Merge-таблице, то в столбце _sample_factor могут быть разные значения.
+	if (sample_factor_column_queried)
+		for (auto & stream : res)
+			stream = new AddingConstColumnBlockInputStream<Float64>(
+				stream, new DataTypeFloat64, used_sample_factor, "_sample_factor");
+
 	return res;
 }

@ -548,10 +590,11 @@ BlockInputStreams MergeTreeDataSelectExecutor::spreadMarkRangesAmongThreads(
 				prewhere_column, settings, virt_columns
 			});

-
 			if (i == 0)
+			{
 				/// Выставим приблизительное количество строк только для первого источника
 				static_cast<IProfilingBlockInputStream &>(*res.front()).setTotalRowsApprox(total_rows);
+			}
 		}
 	}
 	else if (sum_marks > 0)
@ -769,7 +812,8 @@ BlockInputStreams MergeTreeDataSelectExecutor::spreadMarkRangesAmongThreadsFinal
 	return res;
 }

-void MergeTreeDataSelectExecutor::createPositiveSignCondition(ExpressionActionsPtr & out_expression, String & out_column, const Context & context) const
+void MergeTreeDataSelectExecutor::createPositiveSignCondition(
+	ExpressionActionsPtr & out_expression, String & out_column, const Context & context) const
 {
 	ASTFunction * function = new ASTFunction;
 	ASTPtr function_ptr = function;
--- a/dbms/src/Storages/MergeTree/PKCondition.cpp
+++ b/dbms/src/Storages/MergeTree/PKCondition.cpp
@ -112,8 +112,8 @@ PKCondition::PKCondition(ASTPtr & query, const Context & context, const NamesAnd
 	}

 	/** Вычисление выражений, зависящих только от констант.
-	 * Чтобы индекс мог использоваться, если написано, например WHERE Date = toDate(now()).
-	 */
+	  * Чтобы индекс мог использоваться, если написано, например WHERE Date = toDate(now()).
+	  */
 	Block block_with_constants = getBlockWithConstants(query, context, all_columns);

 	/// Преобразуем секцию WHERE в обратную польскую строку.
--- a/dbms/src/Storages/MergeTree/ReshardingWorker.cpp
+++ b/dbms/src/Storages/MergeTree/ReshardingWorker.cpp
@ -55,6 +55,7 @@ namespace ErrorCodes
 	extern const int RESHARDING_COORDINATOR_DELETED;
 	extern const int RESHARDING_DISTRIBUTED_JOB_ON_HOLD;
 	extern const int RESHARDING_INVALID_QUERY;
+	extern const int RWLOCK_NO_SUCH_LOCK;
 }

 namespace
@ -182,8 +183,10 @@ ReshardingWorker::ReshardingWorker(const Poco::Util::AbstractConfiguration & con
 	zookeeper->createIfNotExists(distributed_online_path, "");

 	/// Notify that we are online.
-	(void) zookeeper->tryCreate(distributed_online_path + "/" + current_host, "",
+	int32_t code = zookeeper->tryCreate(distributed_online_path + "/" + current_host, "",
 		zkutil::CreateMode::Ephemeral);
+	if ((code != ZOK) && (code != ZNODEEXISTS))
+		throw zkutil::KeeperException(code);

 	distributed_lock_path = distributed_path + "/lock";
 	zookeeper->createIfNotExists(distributed_lock_path, "");
@ -383,6 +386,8 @@ void ReshardingWorker::perform(const Strings & job_nodes)
 					zookeeper->remove(child_full_path);
 				else if (ex.code() == ErrorCodes::RESHARDING_COORDINATOR_DELETED)
 					zookeeper->remove(child_full_path);
+				else if (ex.code() == ErrorCodes::RWLOCK_NO_SUCH_LOCK)
+					zookeeper->remove(child_full_path);
 				else
 					zookeeper->remove(child_full_path);
 			}
@ -410,6 +415,15 @@ void ReshardingWorker::perform(const std::string & job_descriptor)

 	current_job = ReshardingJob{job_descriptor};

+	zkutil::RWLock deletion_lock;
+
+	if (current_job.isCoordinated())
+		deletion_lock = createDeletionLock(current_job.coordinator_id);
+
+	zkutil::RWLock::Guard<zkutil::RWLock::Read, zkutil::RWLock::NonBlocking> guard{deletion_lock};
+	if (!deletion_lock.ownsLock())
+		throw Exception("Coordinator has been deleted", ErrorCodes::RESHARDING_COORDINATOR_DELETED);
+
 	StoragePtr generic_storage = context.getTable(current_job.database_name, current_job.table_name);
 	auto & storage = typeid_cast<StorageReplicatedMergeTree &>(*(generic_storage.get()));
 	current_job.storage = &storage;
@ -451,6 +465,7 @@ void ReshardingWorker::perform(const std::string & job_descriptor)
 			}
 			else if (ex.code() == ErrorCodes::RESHARDING_REMOTE_NODE_ERROR)
 			{
+				deletion_lock.release();
 				hardCleanup();
 			}
 			else if (ex.code() == ErrorCodes::RESHARDING_COORDINATOR_DELETED)
@ -483,6 +498,7 @@ void ReshardingWorker::perform(const std::string & job_descriptor)
 						auto current_host = getFQDNOrHostName();
 						setStatus(current_job.coordinator_id, current_host, STATUS_ERROR);
 					}
+					deletion_lock.release();
 					hardCleanup();
 				}
 			}
@ -514,6 +530,7 @@ void ReshardingWorker::perform(const std::string & job_descriptor)
 					auto current_host = getFQDNOrHostName();
 					setStatus(current_job.coordinator_id, current_host, STATUS_ERROR);
 				}
+				deletion_lock.release();
 				hardCleanup();
 			}
 		}
@ -525,6 +542,7 @@ void ReshardingWorker::perform(const std::string & job_descriptor)
 		throw;
 	}

+	deletion_lock.release();
 	hardCleanup();
 	LOG_DEBUG(log, "Resharding job successfully completed.");
 }
@ -990,12 +1008,6 @@ UInt64 ReshardingWorker::subscribe(const std::string & coordinator_id, const std
 		zookeeper->set(getCoordinatorPath(coordinator_id) + "/increment", toString(block_number + 1));
 	}

-	/// We set up a timeout for this barrier because until we cross it, we don't have
-	/// any guarantee that all the required nodes for this distributed job are online.
-	/// We are inside a lightweight function, so it is not an issue.
-	auto timeout = context.getSettingsRef().resharding_barrier_timeout;
-	createSubscribeBarrier(coordinator_id).enter(timeout);
-
 	return block_number;
 }

@ -1171,7 +1183,7 @@ bool ReshardingWorker::updateOfflineNodesCommon(const std::string & path, const
 	offline.resize(end - offline.begin());

 	for (const auto & node : offline)
-		zookeeper->set(coordinator_id + "/status/" + node,
+		zookeeper->set(getCoordinatorPath(coordinator_id) + "/status/" + node,
 			toString(static_cast<UInt64>(STATUS_ON_HOLD)));

 	return !offline.empty();
@ -1191,6 +1203,7 @@ ReshardingWorker::Status ReshardingWorker::getStatusCommon(const std::string & p
 {
 	/// Note: we don't need any synchronization for the status.
 	/// That's why we don't acquire any read/write lock.
+	/// All the operations are either reads or idempotent writes.

 	auto zookeeper = context.getZooKeeper();

@ -1234,12 +1247,6 @@ void ReshardingWorker::attachJob()

 	auto zookeeper = context.getZooKeeper();

-	/// Check if the corresponding coordinator exists. If it doesn't, throw an exception,
-	/// silently ignore this job, and switch to the next job.
-	if (!zookeeper->exists(getCoordinatorPath(current_job.coordinator_id)))
-		throw Exception("Coordinator " + current_job.coordinator_id + " was deleted. Ignoring",
-			ErrorCodes::RESHARDING_COORDINATOR_DELETED);
-
 	auto status = getStatus();

 	if (status == STATUS_ERROR)
@ -1479,21 +1486,6 @@ zkutil::RWLock ReshardingWorker::createDeletionLock(const std::string & coordina
 	return lock;
 }

-zkutil::SingleBarrier ReshardingWorker::createSubscribeBarrier(const std::string & coordinator_id)
-{
-	auto zookeeper = context.getZooKeeper();
-
-	auto node_count = zookeeper->get(getCoordinatorPath(coordinator_id) + "/node_count");
-
-	zkutil::SingleBarrier subscribe_barrier{zookeeper, getCoordinatorPath(coordinator_id) + "/subscribe_barrier",
-		std::stoull(node_count)};
-	zkutil::SingleBarrier::CancellationHook hook = std::bind(&ReshardingWorker::abortCoordinatorIfRequested, this,
-		coordinator_id);
-	subscribe_barrier.setCancellationHook(hook);
-
-	return subscribe_barrier;
-}
-
 zkutil::SingleBarrier ReshardingWorker::createCheckBarrier(const std::string & coordinator_id)
 {
 	auto zookeeper = context.getZooKeeper();
--- a/dbms/src/Storages/StorageBuffer.cpp
+++ b/dbms/src/Storages/StorageBuffer.cpp
@ -125,7 +125,13 @@ BlockInputStreams StorageBuffer::read(
 		if (destination.get() == this)
 			throw Exception("Destination table is myself. Read will cause infinite loop.", ErrorCodes::INFINITE_LOOP);

-		streams_from_dst = destination->read(column_names, query, context, settings, processed_stage, max_block_size, threads);
+		/** Отключаем оптимизацию "перенос в PREWHERE",
+		  *  так как Buffer не поддерживает PREWHERE.
+		  */
+		Settings modified_settings = settings;
+		modified_settings.optimize_move_to_prewhere = false;
+
+		streams_from_dst = destination->read(column_names, query, context, modified_settings, processed_stage, max_block_size, threads);
 	}

 	BlockInputStreams streams_from_buffers;
--- a/dbms/src/Storages/StorageDistributed.cpp
+++ b/dbms/src/Storages/StorageDistributed.cpp
@ -246,6 +246,8 @@ void StorageDistributed::reshardPartitions(ASTPtr query, const String & database

 	std::string coordinator_id = resharding_worker.createCoordinator(cluster);

+	std::atomic<bool> has_notified_error{false};
+
 	try
 	{
 		/// Создать запрос ALTER TABLE ... RESHARD PARTITION ... COORDINATE WITH ...
@ -317,7 +319,26 @@ void StorageDistributed::reshardPartitions(ASTPtr query, const String & database
 		BlockInputStreams streams = ClusterProxy::Query(alter_query_constructor, cluster, alter_query_ptr,
 			context, settings, enable_shard_multiplexing).execute();

-		streams[0] = new UnionBlockInputStream<>(streams, nullptr, settings.max_distributed_connections);
+		/// This callback is called if an exception has occurred while attempting to read a block
+		/// from a shard. This is to avoid a potential deadlock if other shards are waiting
+		/// inside a barrier. Actually, even without this solution, we would avoid such a deadlock
+		/// because we would eventually timeout while trying to read blocks from these other shards.
+		/// Nevertheless this is not the ideal way of sorting out this issue.
+		auto exception_callback = [&resharding_worker, coordinator_id, &has_notified_error]()
+		{
+			try
+			{
+				resharding_worker.setStatus(coordinator_id, ReshardingWorker::STATUS_ERROR);
+				has_notified_error = true;
+			}
+			catch (...)
+			{
+				tryLogCurrentException(__PRETTY_FUNCTION__);
+			}
+		};
+
+		streams[0] = new UnionBlockInputStream<>(streams, nullptr, settings.max_distributed_connections,
+			exception_callback);
 		streams.resize(1);

 		auto stream_ptr = dynamic_cast<IProfilingBlockInputStream *>(&*streams[0]);
@ -330,7 +351,8 @@ void StorageDistributed::reshardPartitions(ASTPtr query, const String & database
 		while (!stream.isCancelled() && stream.read())
 			;

-		stream.readSuffix();
+		if (!stream.isCancelled())
+			stream.readSuffix();
 	}
 	catch (...)
 	{
@ -338,7 +360,8 @@ void StorageDistributed::reshardPartitions(ASTPtr query, const String & database

 		try
 		{
-			resharding_worker.setStatus(coordinator_id, ReshardingWorker::STATUS_ERROR);
+			if (!has_notified_error)
+				resharding_worker.setStatus(coordinator_id, ReshardingWorker::STATUS_ERROR);
 			resharding_worker.deleteCoordinator(coordinator_id);
 		}
 		catch (...)
--- a/dbms/src/Storages/StorageReplicatedMergeTree.cpp
+++ b/dbms/src/Storages/StorageReplicatedMergeTree.cpp
@ -81,6 +81,7 @@ namespace ErrorCodes
 	extern const int RESHARDING_NO_COORDINATOR_MEMBERSHIP;
 	extern const int RESHARDING_ALREADY_SUBSCRIBED;
 	extern const int RESHARDING_INVALID_QUERY;
+	extern const int RWLOCK_NO_SUCH_LOCK;
 }


@ -3507,7 +3508,7 @@ void StorageReplicatedMergeTree::reshardPartitions(ASTPtr query, const String &
 		if (has_coordinator)
 		{
 			coordinator_id = coordinator.get<const String &>();
-			deletion_lock = std::move(resharding_worker.createDeletionLock(coordinator_id));
+			deletion_lock = resharding_worker.createDeletionLock(coordinator_id);
 		}

 		zkutil::RWLock::Guard<zkutil::RWLock::Read, zkutil::RWLock::NonBlocking> guard{deletion_lock};
@ -3613,6 +3614,7 @@ void StorageReplicatedMergeTree::reshardPartitions(ASTPtr query, const String &
 			{
 				/// Degenerate case: we are the only participating node.
 				/// All our jobs are uncoordinated.
+				deletion_lock.release();
 				resharding_worker.deleteCoordinator(coordinator_id);
 				uncoordinated_begin = partition_list.cbegin();
 			}
@ -3672,9 +3674,18 @@ void StorageReplicatedMergeTree::reshardPartitions(ASTPtr query, const String &
 				(ex.code() == ErrorCodes::RESHARDING_ALREADY_SUBSCRIBED) ||
 				(ex.code() == ErrorCodes::RESHARDING_INVALID_QUERY))
 			{
-				/// Theoretically any of these errors may have occurred because a user
-				/// has willfully attempted to botch an ongoing distributed resharding job.
-				/// Consequently we don't take them into account.
+				/// Any of these errors occurs only when a user attempts to send
+				/// manually a query ALTER TABLE ... RESHARD ... that specifies
+				/// the parameter COORDINATE WITH, in spite of the fact that no user
+				/// should ever use this parameter. Since taking into account such
+				/// errors may botch an ongoing distributed resharding job, we
+				/// intentionally ignore them.
+			}
+			else if ((ex.code() == ErrorCodes::RWLOCK_NO_SUCH_LOCK) ||
+				(ex.code() == ErrorCodes::RESHARDING_COORDINATOR_DELETED))
+			{
+				/// For any reason the coordinator has disappeared. So obviously
+				/// we don't have any means to notify other nodes of an error.
 			}

 			else if (ex.code() == ErrorCodes::RESHARDING_COORDINATOR_DELETED)
--- a/dbms/src/Storages/VirtualColumnFactory.cpp
+++ b/dbms/src/Storages/VirtualColumnFactory.cpp
@ -27,10 +27,11 @@ bool VirtualColumnFactory::hasColumn(const String & name)

 DataTypePtr VirtualColumnFactory::tryGetType(const String & name)
 {
-	if (name == "_table")		return new DataTypeString;
-	if (name == "_part")		return new DataTypeString;
-	if (name == "_part_index")	return new DataTypeUInt64;
-	if (name == "_replicated")	return new DataTypeUInt8;
+	if (name == "_table")			return new DataTypeString;
+	if (name == "_part")			return new DataTypeString;
+	if (name == "_part_index")		return new DataTypeUInt64;
+	if (name == "_sample_factor")	return new DataTypeFloat64;
+	if (name == "_replicated")		return new DataTypeUInt8;
 	return nullptr;
 }

--- a/dbms/tests/clickhouse-test
+++ b/dbms/tests/clickhouse-test
@ -54,7 +54,7 @@ fi


 # Тесты, зависящие от данных Метрики - не публикуются наружу. Создаём симлинки на внутренний репозиторий. Весьма неудобно.
-QUERIES_PRIVATE_DIR="../../../private/tests/${QUERIES_DIR}"
+QUERIES_PRIVATE_DIR="../../private/tests/${QUERIES_DIR}"
 if [ -d "$QUERIES_PRIVATE_DIR" ]; then
 	for dir in $(ls $QUERIES_PRIVATE_DIR)
 	do
--- a/dbms/tests/queries/0_stateless/00296_multiple_attaches_zookeeper.reference
+++ b/dbms/tests/queries/0_stateless/00296_multiple_attaches_zookeeper.reference
--- a/dbms/tests/queries/0_stateless/00296_multiple_attaches_zookeeper.sql
+++ b/dbms/tests/queries/0_stateless/00296_multiple_attaches_zookeeper.sql
--- a/dbms/tests/queries/0_stateless/00314_sample_factor_virtual_column.reference
+++ b/dbms/tests/queries/0_stateless/00314_sample_factor_virtual_column.reference
@ -0,0 +1,2 @@
+1
+1
--- a/dbms/tests/queries/0_stateless/00314_sample_factor_virtual_column.sql
+++ b/dbms/tests/queries/0_stateless/00314_sample_factor_virtual_column.sql
@ -0,0 +1,18 @@
+DROP TABLE IF EXISTS test.sample1;
+DROP TABLE IF EXISTS test.sample2;
+DROP TABLE IF EXISTS test.sample_merge;
+
+CREATE TABLE test.sample1 (x UInt64, d Date DEFAULT today()) ENGINE = MergeTree(d, intHash64(x), intHash64(x), 10);
+CREATE TABLE test.sample2 (x UInt64, d Date DEFAULT today()) ENGINE = MergeTree(d, intHash64(x), intHash64(x), 10);
+
+INSERT INTO test.sample1 (x) SELECT number AS x FROM system.numbers LIMIT 1000000;
+INSERT INTO test.sample2 (x) SELECT number AS x FROM system.numbers LIMIT 2000000;
+
+CREATE TABLE test.sample_merge AS test.sample1 ENGINE = Merge(test, '^sample\\d$');
+
+SELECT abs(sum(_sample_factor) - 3000000) / 3000000 < 0.001 FROM test.sample_merge SAMPLE 100000;
+SELECT abs(sum(_sample_factor) - 3000000) / 3000000 < 0.001 FROM merge(test, '^sample\\d$') SAMPLE 100000;
+
+DROP TABLE test.sample1;
+DROP TABLE test.sample2;
+DROP TABLE test.sample_merge;
--- a/debian/rules
+++ b/debian/rules
@ -101,7 +101,7 @@ install: build
 		if [ ! -e "debian/$$DAEMON_PKG-metrika-yandex.postinst" ]; then \
 			echo "# automatically created" > debian/$$DAEMON_PKG-metrika-yandex.postinst; \
 			echo "mkdir -p /etc/$$DAEMON_PKG/conf.d" >> debian/$$DAEMON_PKG-metrika-yandex.postinst; \
-			echo "chown metrika: /etc/$$DAEMON_PKG/conf.d" >> debian/$$DAEMON_PKG-metrika-yandex.postinst; \
+			echo "chown -R metrika: /etc/$$DAEMON_PKG" >> debian/$$DAEMON_PKG-metrika-yandex.postinst; \
 			if [ -e "debian/tmp/etc/init.d/$$DAEMON_PKG-metrika-yandex" ]; then \
 				if echo $$DAEMON_PKG | grep server > /dev/null; then\
 					echo "update-rc.d $$DAEMON_PKG-metrika-yandex defaults > /dev/null || exit \$$?" >> debian/$$DAEMON_PKG-metrika-yandex.postinst; \
@ -112,7 +112,7 @@ install: build
 			\
 		else \
 			echo >> debian/$$DAEMON_PKG-metrika-yandex.postinst; \
-			echo "mkdir -p /etc/$$DAEMON_PKG/conf.d; chown metrika: /etc/$$DAEMON_PKG/conf.d" >> debian/$$DAEMON_PKG-metrika-yandex.postinst; \
+			echo "mkdir -p /etc/$$DAEMON_PKG/conf.d; chown -R metrika: /etc/$$DAEMON_PKG" >> debian/$$DAEMON_PKG-metrika-yandex.postinst; \
 		fi;  \
 	done

--- a/libs/libcommon/include/common/DateLUT.h
+++ b/libs/libcommon/include/common/DateLUT.h
@ -66,7 +66,7 @@ private:

 private:
 	/// Указатель на реализацию для часового пояса по-умолчанию.
-	DateLUTImpl * default_date_lut_impl;
+	std::unique_ptr<DateLUTImpl> default_date_lut_impl;
 	/// Соответствующиая группа часовых поясов по-умолчанию.
 	size_t default_group_id;
 	///
--- a/libs/libcommon/include/common/Test.h
+++ b/libs/libcommon/include/common/Test.h
@ -0,0 +1,125 @@
+#pragma once
+
+#include <stdexcept>
+#include <sstream>
+
+/// Часть функциональности - только для сборки из репозитория Метрики.
+#ifndef NO_METRIKA
+	#include <ssqls/IDbObject.h>
+#else
+	struct IDbObject {};
+#endif
+
+#include <regex>
+#include <DB/Common/StackTrace.h>
+#include <DB/IO/WriteBufferFromString.h>
+
+#include <Poco/ConsoleChannel.h>
+#include <Poco/Logger.h>
+#include <Poco/AutoPtr.h>
+
+
+namespace Test
+{
+	template <class Result, class Reference, class Enable = void>
+	struct Comparator
+	{
+		void check(const Result & result, const Reference & reference, const std::string & check_name = "")
+		{
+			if (result != reference)
+			{
+				std::stringstream ss;
+				if (check_name.size())
+					ss << "Check name: " << check_name << ". ";
+
+				StackTrace stacktrace;
+				ss << "Result ";
+				if (check_name.size())
+					ss << "for \"" << check_name << "\" ";
+
+				ss << "differs from reference" <<
+				". Result: " << result << ", reference: " << reference << "\n. Stacktrace: " << stacktrace.toString();
+				throw std::logic_error(ss.str());
+			}
+		}
+	};
+
+	template <class Result, class Reference, class Enable = void, class ... Args>
+	void compare(const Result & result, const Reference & reference, Args && ... args)
+	{
+		Comparator<Result, Reference> comp;
+		comp.check(result, reference, std::forward<Args>(args)...);
+	}
+
+	template <class ContainerA, class ContainerB>
+	void compareContainers(const ContainerA & result, const ContainerB & reference)
+	{
+		if (result != reference)
+		{
+			std::stringstream ss;
+			ss << "Result differs from reference. Result: {";
+			for (auto a : result)
+				ss << " " << a;
+			ss << " }, reference {";
+			for (auto b : reference)
+				ss << " " << b;
+			ss << " }";
+
+			StackTrace stacktrace;
+			ss << "\n. Stacktrace: " << stacktrace.toString();
+
+			throw std::logic_error(ss.str());
+		}
+	}
+
+	template <class Result, class Reference>
+	struct Comparator<Result, Reference, typename std::enable_if<
+					std::is_base_of<IDbObject, Result>::value &&
+					std::is_base_of<IDbObject, Reference>::value>::type>
+	{
+		void check(const Result & result, const Reference & reference, const std::string field_name_regexp_str = ".*")
+		{
+			std::string res_s;
+			{
+				DB::WriteBufferFromString res_b(res_s);
+				result.writeTSKV(res_b, "", "", "");
+			}
+
+			std::string ref_s;
+			{
+				DB::WriteBufferFromString ref_b(ref_s);
+				reference.writeTSKV(ref_b, "", "", "");
+			}
+
+			size_t ref_pos = 0;
+			size_t res_pos = 0;
+
+			while (ref_pos != std::string::npos && res_pos != std::string::npos)
+			{
+				size_t new_ref_pos = ref_s.find('\t', ref_pos);
+				size_t new_res_pos = res_s.find('\t', res_pos);
+
+				auto ref_field = ref_s.substr(ref_pos,
+											  new_ref_pos != std::string::npos ? new_ref_pos - ref_pos : new_ref_pos);
+
+				if (std::regex_match(ref_field, std::regex(field_name_regexp_str + "=.*")))
+				{
+					auto res_field = res_s.substr(res_pos, new_res_pos != std::string::npos ? new_res_pos - res_pos : new_res_pos);
+					compare(res_field, ref_field);
+				}
+
+				res_pos = new_res_pos != res_s.size() && new_res_pos != std::string::npos ?
+					new_res_pos + 1 : std::string::npos;
+				ref_pos = new_ref_pos != ref_s.size() && new_ref_pos != std::string::npos ?
+					new_ref_pos + 1 : std::string::npos;
+			}
+		}
+	};
+
+	inline void initLogger()
+	{
+		Poco::AutoPtr<Poco::ConsoleChannel> channel = new Poco::ConsoleChannel(std::cerr);
+		Poco::Logger::root().setChannel(channel);
+		Poco::Logger::root().setLevel("trace");
+	}
+};
--- a/libs/libcommon/src/DateLUT.cpp
+++ b/libs/libcommon/src/DateLUT.cpp
@ -84,9 +84,9 @@ DateLUT::DateLUT()
 		throw Poco::Exception("Failed to get default time zone information.");
 	default_group_id = it->second;

-	default_date_lut_impl = new DateLUTImpl(default_time_zone);
+	default_date_lut_impl.reset(new DateLUTImpl(default_time_zone));
 	auto & wrapper = (*date_lut_impl_list)[default_group_id];
-	wrapper.store(default_date_lut_impl, std::memory_order_seq_cst);
+	wrapper.store(default_date_lut_impl.get(), std::memory_order_seq_cst);
 }

 const DateLUTImpl & DateLUT::getImplementation(const std::string & time_zone, size_t group_id) const
--- a/libs/libcommon/src/tests/CMakeLists.txt
+++ b/libs/libcommon/src/tests/CMakeLists.txt
@ -12,6 +12,6 @@ target_link_libraries (date_lut2 common libicui18n.a libicuuc.a libicudata.a dl)
 target_link_libraries (date_lut3 common libicui18n.a libicuuc.a libicudata.a dl)
 target_link_libraries (date_lut4 common libicui18n.a libicuuc.a libicudata.a dl)
 target_link_libraries (multi_version common libboost_thread.a libboost_system.a rt)
-target_link_libraries (json_test statdaemons common libboost_thread.a libboost_system.a rt)
+target_link_libraries (json_test dbms libboost_thread.a libboost_system.a rt)

 add_check (json_test)
--- a/libs/libcommon/src/tests/json_test.cpp
+++ b/libs/libcommon/src/tests/json_test.cpp
@ -1,4 +1,5 @@
-#include <statdaemons/Test.h>
+#define NO_METRIKA
+#include <common/Test.h>
 #include <vector>
 #include <string>
 #include <common/JSON.h>
--- a/libs/libdaemon/include/daemon/BaseDaemon.h
+++ b/libs/libdaemon/include/daemon/BaseDaemon.h
@ -165,8 +165,8 @@ protected:
 	Poco::Event wakeup_event;

 	/// Поток, в котором принимается сигнал HUP/USR1 для закрытия логов.
-	Poco::Thread close_logs_thread;
-	std::unique_ptr<Poco::Runnable> close_logs_listener;
+	Poco::Thread signal_listener_thread;
+	std::unique_ptr<Poco::Runnable> signal_listener;

 	/// Файлы с логами.
 	Poco::AutoPtr<Poco::FileChannel> log_file;
--- a/libs/libdaemon/src/BaseDaemon.cpp
+++ b/libs/libdaemon/src/BaseDaemon.cpp
@ -86,14 +86,31 @@ struct Pipe

 	Pipe()
 	{
+		read_fd = -1;
+		write_fd = -1;
+
 		if (0 != pipe(fds))
 			DB::throwFromErrno("Cannot create pipe");
 	}

+	void close()
+	{
+		if (-1 != read_fd)
+		{
+			::close(read_fd);
+			read_fd = -1;
+		}
+
+		if (-1 != write_fd)
+		{
+			::close(write_fd);
+			write_fd = -1;
+		}
+	}
+
 	~Pipe()
 	{
-		close(fds[0]);
-		close(fds[1]);
+		close();
 	}
 };

@ -486,7 +503,13 @@ private:

 /// Для создания и уничтожения unique_ptr, который в заголовочном файле объявлен от incomplete type.
 BaseDaemon::BaseDaemon() = default;
-BaseDaemon::~BaseDaemon() = default;
+
+
+BaseDaemon::~BaseDaemon()
+{
+	signal_pipe.close();
+	signal_listener_thread.join();
+}


 void BaseDaemon::terminate()
@ -760,8 +783,8 @@ void BaseDaemon::initialize(Application& self)
 	/// Выведем ревизию демона
 	logRevision();

-	close_logs_listener.reset(new SignalListener);
-	close_logs_thread.start(*close_logs_listener);
+	signal_listener.reset(new SignalListener);
+	signal_listener_thread.start(*signal_listener);

 	graphite_writer.reset(new GraphiteWriter("graphite"));
 }
--- a/libs/libzkutil/src/RWLock.cpp
+++ b/libs/libzkutil/src/RWLock.cpp
@ -10,6 +10,7 @@ namespace ErrorCodes

 extern const int LOGICAL_ERROR;
 extern const int RWLOCK_ALREADY_HELD;
+extern const int RWLOCK_NO_SUCH_LOCK;
 extern const int ABORTED;

 }
@ -57,7 +58,17 @@ RWLock::RWLock(ZooKeeperPtr & zookeeper_, const std::string & path_)
 {
 	int32_t code = zookeeper->tryCreate(path, "", CreateMode::Persistent);
 	if ((code != ZOK) && (code != ZNODEEXISTS))
-		throw KeeperException(code);
+	{
+		if (code == ZNONODE)
+			throw DB::Exception("No such lock", DB::ErrorCodes::RWLOCK_NO_SUCH_LOCK);
+		else
+			throw KeeperException(code);
+	}
+}
+
+RWLock::operator bool() const
+{
+	return zookeeper && !path.empty();
 }

 RWLock::operator bool() const
@ -117,13 +128,23 @@ void RWLock::acquireImpl(Mode mode)
 	try
 	{
 		/// Enqueue a new request for a lock.
-		key = zookeeper->create(path + "/" + Prefix<lock_type>::name,
-			"", CreateMode::EphemeralSequential);
+		int32_t code = zookeeper->tryCreate(path + "/" + Prefix<lock_type>::name,
+			"", CreateMode::EphemeralSequential, key);
+		if (code == ZNONODE)
+			throw DB::Exception("No such lock", DB::ErrorCodes::RWLOCK_NO_SUCH_LOCK);
+		else if (code != ZOK)
+			throw KeeperException(code);
+
 		key = key.substr(path.length() + 1);

 		while (true)
 		{
-			auto children = zookeeper->getChildren(path);
+			std::vector<std::string> children;
+			int32_t code = zookeeper->tryGetChildren(path, children);
+			if (code == ZNONODE)
+				throw DB::Exception("No such lock", DB::ErrorCodes::RWLOCK_NO_SUCH_LOCK);
+			else if (code != ZOK)
+				throw KeeperException(code);

 			std::sort(children.begin(), children.end(), nodeQueueCmp);
 			auto it = std::lower_bound(children.cbegin(), children.cend(), key, nodeQueueCmp);
@ -168,7 +189,12 @@ void RWLock::acquireImpl(Mode mode)

 			if (mode == NonBlocking)
 			{
-				zookeeper->remove(path + "/" + key);
+				int32_t code = zookeeper->tryRemove(path + "/" + key);
+				if (code == ZNONODE)
+					throw DB::Exception("No such lock", DB::ErrorCodes::RWLOCK_NO_SUCH_LOCK);
+				else if (code != ZOK)
+					throw KeeperException(code);
+
 				key.clear();
 				break;
 			}
--- a/1
+++ b/1
@ -1 +0,0 @@
-Subproject commit f0dd35eadabb7e7c9aa2ab203d54abed693e9b80
--- a/3
+++ b/3
@ -6,6 +6,9 @@ CONTROL=debian/control
 CHLOG=debian/changelog
 CHDATE=$(LC_ALL=C date -R | sed -e 's/,/\\,/g') # Заменим запятую на '\,'

+# Собирать пакет с конфигурационными файлами для Яндекс.Метрики.
+BUILD_PACKAGE_FOR_METRIKA=$([ -f 'private/Server/metrika/config.xml' ] && echo 'yes')
+
 # Список демонов для сборки может быть указан в аргументах командной строки.
 if [ $# -gt 0 ]
 then
				`@ -1 +0,0 @@`
				`Subproject commit f0dd35eadabb7e7c9aa2ab203d54abed693e9b80`