diff --git a/dbms/include/DB/Core/ErrorCodes.h b/dbms/include/DB/Core/ErrorCodes.h
index 11bf7f6576a..82fa14c4cde 100644
--- a/dbms/include/DB/Core/ErrorCodes.h
+++ b/dbms/include/DB/Core/ErrorCodes.h
@@ -1,5 +1,4 @@
-#ifndef DBMS_CORE_ERROR_CODES_H
-#define DBMS_CORE_ERROR_CODES_H
+#pragma once
 
 
 namespace DB
@@ -66,9 +65,8 @@ namespace ErrorCodes
 		TABLE_ALREADY_EXISTS,
 		TABLE_METADATA_ALREADY_EXISTS,
 		ILLEGAL_TYPE_OF_COLUMN_FOR_FILTER,
+		UNKNOWN_TABLE
 	};
 }
 
 }
-
-#endif
diff --git a/dbms/include/DB/DataStreams/ExpressionBlockInputStream.h b/dbms/include/DB/DataStreams/ExpressionBlockInputStream.h
index b3069fc42b2..db152000289 100644
--- a/dbms/include/DB/DataStreams/ExpressionBlockInputStream.h
+++ b/dbms/include/DB/DataStreams/ExpressionBlockInputStream.h
@@ -20,7 +20,7 @@ using Poco::SharedPtr;
 class ExpressionBlockInputStream : public IBlockInputStream
 {
 public:
-	ExpressionBlockInputStream(SharedPtr<IBlockInputStream> input_, SharedPtr<Expression> expression_)
+	ExpressionBlockInputStream(BlockInputStreamPtr input_, SharedPtr<Expression> expression_)
 		: input(input_), expression(expression_) {}
 
 	Block read()
@@ -30,11 +30,11 @@ public:
 			return res;
 
 		expression->execute(res);
-		return res;
+		return expression->projectResult(res);
 	}
 
 private:
-	SharedPtr<IBlockInputStream> input;
+	BlockInputStreamPtr input;
 	SharedPtr<Expression> expression;
 };
 
diff --git a/dbms/include/DB/DataStreams/FilterBlockInputStream.h b/dbms/include/DB/DataStreams/FilterBlockInputStream.h
index f5b86bc52f2..1dcdd544071 100644
--- a/dbms/include/DB/DataStreams/FilterBlockInputStream.h
+++ b/dbms/include/DB/DataStreams/FilterBlockInputStream.h
@@ -19,11 +19,11 @@ class FilterBlockInputStream : public IBlockInputStream
 {
 public:
 	/// filter_column_ - номер столбца с условиями фильтрации
-	FilterBlockInputStream(SharedPtr<IBlockInputStream> input_, size_t filter_column_);
+	FilterBlockInputStream(BlockInputStreamPtr input_, size_t filter_column_);
 	Block read();
 
 private:
-	SharedPtr<IBlockInputStream> input;
+	BlockInputStreamPtr input;
 	size_t filter_column;
 };
 
diff --git a/dbms/include/DB/DataStreams/IBlockInputStream.h b/dbms/include/DB/DataStreams/IBlockInputStream.h
index f5b3c44bfc6..27f61537e40 100644
--- a/dbms/include/DB/DataStreams/IBlockInputStream.h
+++ b/dbms/include/DB/DataStreams/IBlockInputStream.h
@@ -1,5 +1,6 @@
-#ifndef DBMS_DATA_STREAMS_IBLOCKINPUTSTREAM_H
-#define DBMS_DATA_STREAMS_IBLOCKINPUTSTREAM_H
+#pragma once
+
+#include <Poco/SharedPtr.h>
 
 #include <DB/Core/Block.h>
 
@@ -7,6 +8,9 @@
 namespace DB
 {
 
+using Poco::SharedPtr;
+
+
 /** Интерфейс потока для чтения данных по блокам из БД.
   * Реляционные операции предполагается делать также реализациями этого интерфейса.
   */
@@ -22,6 +26,8 @@ public:
 	virtual ~IBlockInputStream() {}
 };
 
+
+typedef SharedPtr<IBlockInputStream> BlockInputStreamPtr;
+
 }
 
-#endif
diff --git a/dbms/include/DB/DataStreams/IBlockOutputStream.h b/dbms/include/DB/DataStreams/IBlockOutputStream.h
index 8f1d2b45910..ba61bc72edb 100644
--- a/dbms/include/DB/DataStreams/IBlockOutputStream.h
+++ b/dbms/include/DB/DataStreams/IBlockOutputStream.h
@@ -1,5 +1,6 @@
-#ifndef DBMS_DATA_STREAMS_IBLOCKOUTPUTSTREAM_H
-#define DBMS_DATA_STREAMS_IBLOCKOUTPUTSTREAM_H
+#pragma once
+
+#include <Poco/SharedPtr.h>
 
 #include <DB/Core/Block.h>
 
@@ -7,6 +8,9 @@
 namespace DB
 {
 
+using Poco::SharedPtr;
+
+
 /** Интерфейс потока для записи данных в БД или в сеть, или в консоль и т. п.
   */
 class IBlockOutputStream
@@ -20,6 +24,6 @@ public:
 	virtual ~IBlockOutputStream() {}
 };
 
-}
+typedef SharedPtr<IBlockOutputStream> BlockOutputStreamPtr;
 
-#endif
+}
diff --git a/dbms/include/DB/DataStreams/LimitBlockInputStream.h b/dbms/include/DB/DataStreams/LimitBlockInputStream.h
index 9479d27e06e..84f97077cc8 100644
--- a/dbms/include/DB/DataStreams/LimitBlockInputStream.h
+++ b/dbms/include/DB/DataStreams/LimitBlockInputStream.h
@@ -17,11 +17,11 @@ using Poco::SharedPtr;
 class LimitBlockInputStream : public IBlockInputStream
 {
 public:
-	LimitBlockInputStream(SharedPtr<IBlockInputStream> input_, size_t limit_, size_t offset_ = 0);
+	LimitBlockInputStream(BlockInputStreamPtr input_, size_t limit_, size_t offset_ = 0);
 	Block read();
 
 private:
-	SharedPtr<IBlockInputStream> input;
+	BlockInputStreamPtr input;
 	size_t limit;
 	size_t offset;
 	size_t pos;
diff --git a/dbms/include/DB/DataStreams/ProfilingBlockInputStream.h b/dbms/include/DB/DataStreams/ProfilingBlockInputStream.h
index b3024b5c8a6..edd6b9159d4 100644
--- a/dbms/include/DB/DataStreams/ProfilingBlockInputStream.h
+++ b/dbms/include/DB/DataStreams/ProfilingBlockInputStream.h
@@ -37,7 +37,7 @@ struct BlockStreamProfileInfo
 class ProfilingBlockInputStream : public IBlockInputStream
 {
 public:
-	ProfilingBlockInputStream(SharedPtr<IBlockInputStream> in_)
+	ProfilingBlockInputStream(BlockInputStreamPtr in_)
 		: in(in_) {}
 	
 	Block read();
@@ -45,7 +45,7 @@ public:
 	const BlockStreamProfileInfo & getInfo() const;
 
 private:
-	SharedPtr<IBlockInputStream> in;
+	BlockInputStreamPtr in;
 	BlockStreamProfileInfo info;
 };
 
diff --git a/dbms/include/DB/DataStreams/RowInputStreamFromBlockInputStream.h b/dbms/include/DB/DataStreams/RowInputStreamFromBlockInputStream.h
index cf43c16753b..27059a0b0d6 100644
--- a/dbms/include/DB/DataStreams/RowInputStreamFromBlockInputStream.h
+++ b/dbms/include/DB/DataStreams/RowInputStreamFromBlockInputStream.h
@@ -1,7 +1,4 @@
-#ifndef DBMS_DATA_STREAMS_ROWINPUTSTREAMFROMBLOCKINPUTSTREAM_H
-#define DBMS_DATA_STREAMS_ROWINPUTSTREAMFROMBLOCKINPUTSTREAM_H
-
-#include <Poco/SharedPtr.h>
+#pragma once
 
 #include <DB/DataStreams/IBlockInputStream.h>
 #include <DB/DataStreams/IRowInputStream.h>
@@ -10,8 +7,6 @@
 namespace DB
 {
 
-using Poco::SharedPtr;
-
 
 /** Преобразует поток для чтения данных по блокам в поток для чтения данных по строкам.
   */
@@ -30,5 +25,3 @@ private:
 };
 
 }
-
-#endif
diff --git a/dbms/include/DB/Interpreters/Expression.h b/dbms/include/DB/Interpreters/Expression.h
index a5f16d0e145..359a25d60e9 100644
--- a/dbms/include/DB/Interpreters/Expression.h
+++ b/dbms/include/DB/Interpreters/Expression.h
@@ -26,8 +26,14 @@ public:
 
 	/** Выполнить выражение над блоком. Блок должен содержать все столбцы - идентификаторы.
 	  * Функция добавляет в блок новые столбцы - результаты вычислений.
+	  * part_id - какую часть выражения вычислять.
 	  */
-	void execute(Block & block);
+	void execute(Block & block, unsigned part_id = 0);
+
+	/** Взять из блока с промежуточными результатами вычислений только столбцы, представляющие собой конечный результат.
+	  * Вернуть новый блок, в котором эти столбцы расположены в правильном порядке.
+	  */
+	Block projectResult(Block & block);
 
 	/** Получить список типов столбцов результата.
 	  */
@@ -61,14 +67,9 @@ private:
 
 	/** Прописать во всех узлах, что они ещё не вычислены.
 	  */
-	void setNotCalculated(ASTPtr ast);
+	void setNotCalculated(ASTPtr ast, unsigned part_id);
 
-	void executeImpl(ASTPtr ast, Block & block);
-
-	/** Взять из блока с промежуточными результатами вычислений только столбцы, представляющие собой конечный результат.
-	  * Вернуть новый блок, в котором эти столбцы расположены в правильном порядке.
-	  */
-	Block projectResult(ASTPtr ast, Block & block);
+	void executeImpl(ASTPtr ast, Block & block, unsigned part_id);
 
 	void collectFinalColumns(ASTPtr ast, Block & src, Block & dst);
 
diff --git a/dbms/include/DB/Parsers/ASTIdentifier.h b/dbms/include/DB/Parsers/ASTIdentifier.h
index f56adc357fb..08b9f065572 100644
--- a/dbms/include/DB/Parsers/ASTIdentifier.h
+++ b/dbms/include/DB/Parsers/ASTIdentifier.h
@@ -1,5 +1,4 @@
-#ifndef DBMS_PARSERS_ASTIDENTIFIER_H
-#define DBMS_PARSERS_ASTIDENTIFIER_H
+#pragma once
 
 #include <DB/DataTypes/IDataType.h>
 #include <DB/Parsers/IAST.h>
@@ -13,18 +12,27 @@ namespace DB
 class ASTIdentifier : public IAST
 {
 public:
+	enum Kind
+	{
+		Column,
+		Database,
+		Table,
+	};
+	
 	/// имя
 	String name;
-	/// тип
+
+	/// чего идентифицирует этот идентификатор
+	Kind kind;
+
+	/// тип (только для столбцов)
 	DataTypePtr type;
 
 	ASTIdentifier() {}
-	ASTIdentifier(StringRange range_, const String & name_) : IAST(range_), name(name_) {}
+	ASTIdentifier(StringRange range_, const String & name_, Kind kind_ = Column) : IAST(range_), name(name_), kind(kind_) {}
 	
 	/** Получить текст, который идентифицирует этот элемент. */
 	String getID() { return "Identifier_" + name; }
 };
 
 }
-
-#endif
diff --git a/dbms/include/DB/Parsers/IAST.h b/dbms/include/DB/Parsers/IAST.h
index 0771d541f88..23288af8bb2 100644
--- a/dbms/include/DB/Parsers/IAST.h
+++ b/dbms/include/DB/Parsers/IAST.h
@@ -23,12 +23,20 @@ public:
 	typedef std::list<SharedPtr<IAST> > ASTs;
 	ASTs children;
 	StringRange range;
-	/// Было ли соответствующее выражение вычислено.
+
+	/** Было ли соответствующее выражение вычислено.
+	  * Используется, чтобы при обходе графа выражения, не вычислять несколько раз одни и те же узлы.
+	  */
 	bool calculated;
 	
+	/** Идентификатор части выражения. Используется при интерпретации, чтобы вычислять не всё выражение сразу,
+	  *  а по частям (например, сначала WHERE, потом фильтрация, потом всё остальное).
+	  */
+	unsigned part_id;
+	
 
-	IAST() : range(NULL, NULL), calculated(false) {}
-	IAST(StringRange range_) : range(range_), calculated(false) {}
+	IAST() : range(NULL, NULL), calculated(false), part_id(0) {}
+	IAST(StringRange range_) : range(range_), calculated(false), part_id(0) {}
 	virtual ~IAST() {}
 		
 	/** Получить текст, который идентифицирует этот элемент. */
diff --git a/dbms/include/DB/Storages/IStorage.h b/dbms/include/DB/Storages/IStorage.h
index 45cad9d4e87..e25c60b2f29 100644
--- a/dbms/include/DB/Storages/IStorage.h
+++ b/dbms/include/DB/Storages/IStorage.h
@@ -44,7 +44,7 @@ public:
 	  *  (индексы, блокировки и т. п.)
 	  * Возвращает объект, с помощью которого можно последовательно читать данные.
 	  */
-	virtual SharedPtr<IBlockInputStream> read(
+	virtual BlockInputStreamPtr read(
 		const Names & column_names,
 		ASTPtr query,
 		size_t max_block_size = DEFAULT_BLOCK_SIZE)
@@ -56,7 +56,7 @@ public:
 	  * Принимает описание запроса, в котором может содержаться информация о методе записи данных.
 	  * Возвращает объект, с помощью которого можно последовательно писать данные.
 	  */
-	virtual SharedPtr<IBlockOutputStream> write(
+	virtual BlockOutputStreamPtr write(
 		ASTPtr query)
 	{
 		throw Exception("Method write() is not supported by storage " + getName(), ErrorCodes::NOT_IMPLEMENTED);
diff --git a/dbms/include/DB/Storages/StorageLog.h b/dbms/include/DB/Storages/StorageLog.h
index 7e11165d891..4d254738167 100644
--- a/dbms/include/DB/Storages/StorageLog.h
+++ b/dbms/include/DB/Storages/StorageLog.h
@@ -91,12 +91,12 @@ public:
 
 	const NamesAndTypes & getColumns() const { return *columns; }
 
-	SharedPtr<IBlockInputStream> read(
+	BlockInputStreamPtr read(
 		const Names & column_names,
 		ASTPtr query,
 		size_t max_block_size = DEFAULT_BLOCK_SIZE);
 
-	SharedPtr<IBlockOutputStream> write(
+	BlockOutputStreamPtr write(
 		ASTPtr query);
 
 private:
diff --git a/dbms/include/DB/Storages/StorageSystemNumbers.h b/dbms/include/DB/Storages/StorageSystemNumbers.h
index 1797a7a0f86..2386de059c1 100644
--- a/dbms/include/DB/Storages/StorageSystemNumbers.h
+++ b/dbms/include/DB/Storages/StorageSystemNumbers.h
@@ -36,7 +36,7 @@ public:
 
 	const NamesAndTypes & getColumns() const { return columns; }
 
-	SharedPtr<IBlockInputStream> read(
+	BlockInputStreamPtr read(
 		const Names & column_names,
 		ASTPtr query,
 		size_t max_block_size = DEFAULT_BLOCK_SIZE);
diff --git a/dbms/include/DB/Storages/StorageSystemOne.h b/dbms/include/DB/Storages/StorageSystemOne.h
new file mode 100644
index 00000000000..6ecc421b479
--- /dev/null
+++ b/dbms/include/DB/Storages/StorageSystemOne.h
@@ -0,0 +1,45 @@
+#pragma once
+
+#include <DB/Storages/IStorage.h>
+
+
+namespace DB
+{
+
+
+class OneValueBlockInputStream : public IBlockInputStream
+{
+public:
+	OneValueBlockInputStream();
+	Block read();
+private:
+	bool has_been_read;
+};
+
+
+/** Реализует хранилище для системной таблицы One.
+  * Таблица содержит единственный столбец dummy UInt8 и единственную строку со значением 0.
+  * Используется, если в запросе не указана таблица.
+  * Аналог таблицы DUAL в Oracle и MySQL.
+  */
+class StorageSystemOne : public IStorage
+{
+public:
+	StorageSystemOne(const std::string & name_);
+	
+	std::string getName() const { return "SystemOne"; }
+	std::string getTableName() const { return "One"; }
+
+	const NamesAndTypes & getColumns() const { return columns; }
+
+	BlockInputStreamPtr read(
+		const Names & column_names,
+		ASTPtr query,
+		size_t max_block_size = DEFAULT_BLOCK_SIZE);
+
+private:
+	const std::string name;
+	NamesAndTypes columns;
+};
+
+}
diff --git a/dbms/src/DataStreams/FilterBlockInputStream.cpp b/dbms/src/DataStreams/FilterBlockInputStream.cpp
index 059e70b0508..4ecb0feab61 100644
--- a/dbms/src/DataStreams/FilterBlockInputStream.cpp
+++ b/dbms/src/DataStreams/FilterBlockInputStream.cpp
@@ -6,7 +6,7 @@
 namespace DB
 {
 
-FilterBlockInputStream::FilterBlockInputStream(SharedPtr<IBlockInputStream> input_, size_t filter_column_)
+FilterBlockInputStream::FilterBlockInputStream(BlockInputStreamPtr input_, size_t filter_column_)
 	: input(input_), filter_column(filter_column_)
 {
 }
diff --git a/dbms/src/DataStreams/LimitBlockInputStream.cpp b/dbms/src/DataStreams/LimitBlockInputStream.cpp
index 2d653be7517..e174a1f91ac 100644
--- a/dbms/src/DataStreams/LimitBlockInputStream.cpp
+++ b/dbms/src/DataStreams/LimitBlockInputStream.cpp
@@ -8,7 +8,7 @@ namespace DB
 
 using Poco::SharedPtr;
 
-LimitBlockInputStream::LimitBlockInputStream(SharedPtr<IBlockInputStream> input_, size_t limit_, size_t offset_)
+LimitBlockInputStream::LimitBlockInputStream(BlockInputStreamPtr input_, size_t limit_, size_t offset_)
 	: input(input_), limit(limit_), offset(offset_), pos(0)
 {
 }
diff --git a/dbms/src/Interpreters/Expression.cpp b/dbms/src/Interpreters/Expression.cpp
index 00fdb0980a6..54109c5c945 100644
--- a/dbms/src/Interpreters/Expression.cpp
+++ b/dbms/src/Interpreters/Expression.cpp
@@ -23,11 +23,14 @@ void Expression::addSemantic(ASTPtr ast)
 	}
 	else if (ASTIdentifier * node = dynamic_cast<ASTIdentifier *>(&*ast))
 	{
-		NamesAndTypes::const_iterator it = context.columns.find(node->name);
-		if (it == context.columns.end())
-			throw Exception("Unknown identifier " + node->name, ErrorCodes::UNKNOWN_IDENTIFIER);
+		if (node->kind == ASTIdentifier::Column)
+		{
+			NamesAndTypes::const_iterator it = context.columns.find(node->name);
+			if (it == context.columns.end())
+				throw Exception("Unknown identifier " + node->name, ErrorCodes::UNKNOWN_IDENTIFIER);
 
-		node->type = it->second;
+			node->type = it->second;
+		}
 	}
 	else if (ASTLiteral * node = dynamic_cast<ASTLiteral *>(&*ast))
 	{
@@ -104,30 +107,30 @@ void Expression::glueTreeImpl(ASTPtr ast, Subtrees & subtrees)
 }
 
 
-void Expression::setNotCalculated(ASTPtr ast)
+void Expression::setNotCalculated(ASTPtr ast, unsigned part_id)
 {
-	ast->calculated = false;
+	if (ast->part_id == part_id)
+		ast->calculated = false;
 	for (ASTs::iterator it = ast->children.begin(); it != ast->children.end(); ++it)
-		setNotCalculated(*it);
+		setNotCalculated(*it, part_id);
 }
 
 
-void Expression::execute(Block & block)
+void Expression::execute(Block & block, unsigned part_id)
 {
-	setNotCalculated(ast);
-	executeImpl(ast, block);
-	block = projectResult(ast, block);
+	setNotCalculated(ast, part_id);
+	executeImpl(ast, block, part_id);
 }
 
 
-void Expression::executeImpl(ASTPtr ast, Block & block)
+void Expression::executeImpl(ASTPtr ast, Block & block, unsigned part_id)
 {
 	/// Обход в глубину
 
 	for (ASTs::iterator it = ast->children.begin(); it != ast->children.end(); ++it)
-		executeImpl(*it, block);
+		executeImpl(*it, block, part_id);
 
-	if (ast->calculated)
+	if (ast->calculated || ast->part_id != part_id)
 		return;
 
 	/** Столбцы из таблицы уже загружены в блок.
@@ -186,7 +189,7 @@ void Expression::executeImpl(ASTPtr ast, Block & block)
 }
 
 
-Block Expression::projectResult(ASTPtr ast, Block & block)
+Block Expression::projectResult(Block & block)
 {
 	Block res;
 	collectFinalColumns(ast, block, res);
@@ -197,7 +200,10 @@ Block Expression::projectResult(ASTPtr ast, Block & block)
 void Expression::collectFinalColumns(ASTPtr ast, Block & src, Block & dst)
 {
 	if (ASTIdentifier * ident = dynamic_cast<ASTIdentifier *>(&*ast))
-		dst.insert(src.getByName(ident->name));
+	{
+		if (ident->kind == ASTIdentifier::Column)
+			dst.insert(src.getByName(ident->name));
+	}
 	else if (dynamic_cast<ASTLiteral *>(&*ast))
 		dst.insert(src.getByName(ast->getTreeID()));
 	else if (ASTFunction * func = dynamic_cast<ASTFunction *>(&*ast))
diff --git a/dbms/src/Interpreters/tests/expression.cpp b/dbms/src/Interpreters/tests/expression.cpp
index f543adc4508..f19ac001f29 100644
--- a/dbms/src/Interpreters/tests/expression.cpp
+++ b/dbms/src/Interpreters/tests/expression.cpp
@@ -179,6 +179,7 @@ int main(int argc, char ** argv)
 			stopwatch.start();
 
 			expression.execute(block);
+			block = expression.projectResult(block);
 
 			stopwatch.stop();
 			std::cout << std::fixed << std::setprecision(2)
diff --git a/dbms/src/Parsers/ParserSelectQuery.cpp b/dbms/src/Parsers/ParserSelectQuery.cpp
index 3a5deeaec6f..28c1e8c2074 100644
--- a/dbms/src/Parsers/ParserSelectQuery.cpp
+++ b/dbms/src/Parsers/ParserSelectQuery.cpp
@@ -1,4 +1,5 @@
 #include <DB/Parsers/ASTSelectQuery.h>
+#include <DB/Parsers/ASTIdentifier.h>
 #include <DB/Parsers/IParserBase.h>
 #include <DB/Parsers/CommonParsers.h>
 #include <DB/Parsers/ExpressionElementParsers.h>
@@ -65,6 +66,9 @@ bool ParserSelectQuery::parseImpl(Pos & pos, Pos end, ASTPtr & node, String & ex
 
 			ws.ignore(pos, end);
 		}
+
+		dynamic_cast<ASTIdentifier &>(*select_query->database).kind = ASTIdentifier::Database;
+		dynamic_cast<ASTIdentifier &>(*select_query->table).kind = ASTIdentifier::Table;
 	}
 
 	/// WHERE expr
diff --git a/dbms/src/Storages/StorageLog.cpp b/dbms/src/Storages/StorageLog.cpp
index 60356368d0e..878cd24c58f 100644
--- a/dbms/src/Storages/StorageLog.cpp
+++ b/dbms/src/Storages/StorageLog.cpp
@@ -84,7 +84,7 @@ StorageLog::StorageLog(const std::string & path_, const std::string & name_, Sha
 }
 
 
-SharedPtr<IBlockInputStream> StorageLog::read(
+BlockInputStreamPtr StorageLog::read(
 	const Names & column_names,
 	ASTPtr query,
 	size_t max_block_size)
@@ -94,7 +94,7 @@ SharedPtr<IBlockInputStream> StorageLog::read(
 }
 
 	
-SharedPtr<IBlockOutputStream> StorageLog::write(
+BlockOutputStreamPtr StorageLog::write(
 	ASTPtr query)
 {
 	return new LogBlockOutputStream(*this);
diff --git a/dbms/src/Storages/StorageSystemNumbers.cpp b/dbms/src/Storages/StorageSystemNumbers.cpp
index 351e6533e32..0847b1d5195 100644
--- a/dbms/src/Storages/StorageSystemNumbers.cpp
+++ b/dbms/src/Storages/StorageSystemNumbers.cpp
@@ -46,7 +46,7 @@ StorageSystemNumbers::StorageSystemNumbers(const std::string & name_)
 }
 
 
-SharedPtr<IBlockInputStream> StorageSystemNumbers::read(
+BlockInputStreamPtr StorageSystemNumbers::read(
 	const Names & column_names, ASTPtr query, size_t max_block_size)
 {
 	check(column_names);
diff --git a/dbms/src/Storages/StorageSystemOne.cpp b/dbms/src/Storages/StorageSystemOne.cpp
new file mode 100644
index 00000000000..9e081768446
--- /dev/null
+++ b/dbms/src/Storages/StorageSystemOne.cpp
@@ -0,0 +1,51 @@
+#include <DB/Core/Exception.h>
+#include <DB/Core/ErrorCodes.h>
+
+#include <DB/Columns/ColumnsNumber.h>
+
+#include <DB/DataTypes/DataTypesNumberFixed.h>
+
+#include <DB/Storages/StorageSystemOne.h>
+
+
+namespace DB
+{
+
+
+OneValueBlockInputStream::OneValueBlockInputStream() : has_been_read(false)
+{
+}
+
+
+Block OneValueBlockInputStream::read()
+{
+	Block res;
+	if (has_been_read)
+		return res;
+
+	has_been_read = true;
+	ColumnWithNameAndType col;
+	col.name = "dummy";
+	col.type = new DataTypeUInt8;
+	col.column = new ColumnConstUInt8(0, 1);
+	res.insert(col);
+	return res;
+}
+
+
+StorageSystemOne::StorageSystemOne(const std::string & name_)
+	: name(name_)
+{
+	columns["dummy"] = new DataTypeUInt8;
+}
+
+
+BlockInputStreamPtr StorageSystemOne::read(
+	const Names & column_names, ASTPtr query, size_t max_block_size)
+{
+	check(column_names);
+	return new OneValueBlockInputStream();
+}
+
+
+}