dbms: development [#CONV-2944].

dbms/include/DB/Core/ErrorCodes.h

@@ -85,6 +85,7 @@ namespace ErrorCodes
 		CANNOT_CLOSE_FILE,
 		UNKNOWN_TYPE_OF_QUERY,
 		INCORRECT_FILE_NAME,
+		INCORRECT_QUERY,
 	};
 }
 

dbms/include/DB/Interpreters/Context.h

@@ -11,6 +11,7 @@
 #include <DB/Functions/IFunction.h>
 #include <DB/AggregateFunctions/AggregateFunctionFactory.h>
 #include <DB/DataTypes/DataTypeFactory.h>
+#include <DB/Storages/StorageFactory.h>
 
 
 namespace DB
@@ -38,6 +39,7 @@ struct Context
 	SharedPtr<Functions> functions;							/// Обычные функции.
 	AggregateFunctionFactoryPtr aggregate_function_factory; /// Агрегатные функции.
 	DataTypeFactoryPtr data_type_factory;					/// Типы данных.
+	StorageFactoryPtr storage_factory;						/// Движки таблиц.
 	NamesAndTypes columns;									/// Столбцы текущей обрабатываемой таблицы.
 
 	SharedPtr<Poco::FastMutex> mutex;	/// Для доступа и модификации разделяемых объектов.

dbms/include/DB/Parsers/ASTCreateQuery.h

@@ -19,6 +19,8 @@ public:
 	String table;
 	ASTPtr columns;
 	ASTPtr storage;
+	String as_database;
+	String as_table;
 
 	ASTCreateQuery() {}
 	ASTCreateQuery(StringRange range_) : IAST(range_), attach(false) {}

dbms/include/DB/Storages/StorageFactory.h

@@ -0,0 +1,27 @@
+#pragma once
+
+#include <DB/Storages/IStorage.h>
+
+
+namespace DB
+{
+
+using Poco::SharedPtr;
+
+
+/** Позволяет создать таблицу по имени движка.
+  */
+class StorageFactory
+{
+public:
+	StoragePtr get(
+		const String & name,
+		const String & data_path,
+		const String & table_name,
+		SharedPtr<NamesAndTypes> columns) const;
+};
+
+typedef SharedPtr<StorageFactory> StorageFactoryPtr;
+
+
+}

dbms/src/Interpreters/InterpreterCreateQuery.cpp

@@ -19,6 +19,9 @@ StoragePtr InterpreterCreateQuery::execute(ASTPtr query, Context & context)
 
 	String database_name = create.database.empty() ? context.current_database : create.database;
 	String table_name = create.table;
+	String as_database_name = create.as_database.empty() ? context.current_database : create.as_database;
+	String as_table_name = create.as_table;
+	
 	SharedPtr<NamesAndTypes> columns = new NamesAndTypes;
 	String data_path = context.path + "data/" + database_name + "/";	/// TODO: эскейпинг
 	String metadata_path = context.path + "metadata/" + database_name + "/" + table_name + ".sql";
@@ -34,39 +37,38 @@ StoragePtr InterpreterCreateQuery::execute(ASTPtr query, Context & context)
 				throw Exception("Table " + database_name + "." + table_name + " already exists.", ErrorCodes::TABLE_ALREADY_EXISTS);
 		}
 	}
-	
-	ASTExpressionList & columns_list = dynamic_cast<ASTExpressionList &>(*create.columns);
-	for (ASTs::iterator it = columns_list.children.begin(); it != columns_list.children.end(); ++it)
-	{
-		ASTNameTypePair & name_and_type_pair = dynamic_cast<ASTNameTypePair &>(**it);
-		StringRange type_range = name_and_type_pair.type->range;
-		(*columns)[name_and_type_pair.name] = context.data_type_factory->get(String(type_range.first, type_range.second - type_range.first));
-	}
 
-	ASTFunction & storage_expr = dynamic_cast<ASTFunction &>(*create.storage);
-	String storage_str(storage_expr.range.first, storage_expr.range.second - storage_expr.range.first);
-	StoragePtr res;
+	if (!create.as_table.empty()
+		&& ((*context.databases).end() == (*context.databases).find(as_database_name)
+			|| (*context.databases)[as_database_name].end() == (*context.databases)[as_database_name].find(as_table_name)))
+		throw Exception("Table " + as_database_name + "." + as_table_name + " doesn't exist.", ErrorCodes::UNKNOWN_TABLE);
+
+	if (create.columns)
+	{
+		ASTExpressionList & columns_list = dynamic_cast<ASTExpressionList &>(*create.columns);
+		for (ASTs::iterator it = columns_list.children.begin(); it != columns_list.children.end(); ++it)
+		{
+			ASTNameTypePair & name_and_type_pair = dynamic_cast<ASTNameTypePair &>(**it);
+			StringRange type_range = name_and_type_pair.type->range;
+			(*columns)[name_and_type_pair.name] = context.data_type_factory->get(String(type_range.first, type_range.second - type_range.first));
+		}
+	}
+	else if (!create.as_table.empty())
+		columns = new NamesAndTypes((*context.databases)[as_database_name][as_table_name]->getColumns());
+	else
+		throw Exception("Incorrect CREATE query: required list of column descriptions or AS section.", ErrorCodes::INCORRECT_QUERY);
 
 	/// Выбор нужного движка таблицы
 
-	if (storage_expr.name == "Log")
-	{
-		if (storage_expr.arguments)
-			throw Exception("Storage Log doesn't allow parameters", ErrorCodes::STORAGE_DOESNT_ALLOW_PARAMETERS);
-
-		res = new StorageLog(data_path, table_name, columns);
-	}
-	else if (storage_expr.name == "SystemNumbers")
-	{
-		if (storage_expr.arguments)
-			throw Exception("Storage SystemNumbers doesn't allow parameters", ErrorCodes::STORAGE_DOESNT_ALLOW_PARAMETERS);
-		if (columns->size() != 1 || columns->begin()->first != "number" || columns->begin()->second->getName() != "UInt64")
-			throw Exception("Storage SystemNumbers only allows one column with name 'number' and type 'UInt64'", ErrorCodes::ILLEGAL_COLUMN);
-
-		res = new StorageSystemNumbers(table_name);
-	}
+	String storage_name;
+	if (create.storage)
+		storage_name = dynamic_cast<ASTFunction &>(*create.storage).name;
+	else if (!create.as_table.empty())
+		storage_name = (*context.databases)[as_database_name][as_table_name]->getName();
 	else
-		throw Exception("Unknown storage " + storage_str, ErrorCodes::UNKNOWN_STORAGE);
+		throw Exception("Incorrect CREATE query: required ENGINE or AS section.", ErrorCodes::INCORRECT_QUERY);
+		
+	StoragePtr res = context.storage_factory->get(storage_name, data_path, table_name, columns);
 
 	/// Проверка наличия метаданных таблицы на диске и создание метаданных
 
@@ -82,7 +84,13 @@ StoragePtr InterpreterCreateQuery::execute(ASTPtr query, Context & context)
 	else
 	{
 		Poco::FileOutputStream metadata_file(metadata_path);
-		metadata_file << String(create.range.first, create.range.second - create.range.first) << std::endl;
+		metadata_file << "ATTACH TABLE " << database_name << "." << table_name << "\n"
+			<< "(\n";
+
+		for (NamesAndTypes::const_iterator it = columns->begin(); it != columns->end(); ++it)
+			metadata_file << (it != columns->begin() ? ",\n" : "") << "\t" << it->first << " " << it->second->getName();
+			
+		metadata_file << "\n) ENGINE = " << storage_name << "\n";
 	}
 
 	{

dbms/src/Interpreters/tests/select_query.cpp

@@ -13,6 +13,7 @@
 #include <DB/Storages/StorageLog.h>
 #include <DB/Storages/StorageSystemNumbers.h>
 #include <DB/Storages/StorageSystemOne.h>
+#include <DB/Storages/StorageFactory.h>
 
 #include <DB/DataStreams/TabSeparatedRowOutputStream.h>
 #include <DB/DataStreams/copyData.h>
@@ -188,6 +189,7 @@ int main(int argc, char ** argv)
 		
 		context.aggregate_function_factory		= new DB::AggregateFunctionFactory;
 		context.data_type_factory				= new DB::DataTypeFactory;
+		context.storage_factory					= new DB::StorageFactory;
 
 		DB::loadMetadata(context);
 

dbms/src/Parsers/ParserCreateQuery.cpp

@@ -82,6 +82,7 @@ bool ParserCreateQuery::parseImpl(Pos & pos, Pos end, ASTPtr & node, String & ex
 	ParserString s_if("IF", true);
 	ParserString s_not("NOT", true);
 	ParserString s_exists("EXISTS", true);
+	ParserString s_as("AS", true);
 	ParserIdentifier name_p;
 	ParserList columns_p(new ParserNameTypePair, new ParserString(","), false);
 	ParserIdentifierWithOptionalParameters storage_p;
@@ -90,6 +91,8 @@ bool ParserCreateQuery::parseImpl(Pos & pos, Pos end, ASTPtr & node, String & ex
 	ASTPtr table;
 	ASTPtr columns;
 	ASTPtr storage;
+	ASTPtr as_database;
+	ASTPtr as_table;
 	bool attach = false;
 	bool if_not_exists = false;
 
@@ -128,35 +131,58 @@ bool ParserCreateQuery::parseImpl(Pos & pos, Pos end, ASTPtr & node, String & ex
 		ws.ignore(pos, end);
 	}
 
-	if (!s_lparen.ignore(pos, end, expected))
+	/// Список столбцов
+	if (s_lparen.ignore(pos, end, expected))
+	{
+		ws.ignore(pos, end);
+
+		if (!columns_p.parse(pos, end, columns, expected))
+			return false;
+
+		ws.ignore(pos, end);
+
+		if (!s_rparen.ignore(pos, end, expected))
+			return false;
+
+		ws.ignore(pos, end);
+	}
+	else if (s_as.ignore(pos, end, expected))
+	{
+		/// Или AS другая таблица
+		ws.ignore(pos, end);
+
+		if (!name_p.parse(pos, end, as_table, expected))
+			return false;
+
+		ws.ignore(pos, end);
+
+		if (s_dot.ignore(pos, end, expected))
+		{
+			as_database = as_table;
+			if (!name_p.parse(pos, end, as_table, expected))
+				return false;
+
+			ws.ignore(pos, end);
+		}
+	}
+	else
 		return false;
 
-	ws.ignore(pos, end);
+	/// ENGINE
+	if (s_engine.ignore(pos, end, expected))
+	{
+		ws.ignore(pos, end);
 
-	if (!columns_p.parse(pos, end, columns, expected))
-		return false;
+		if (!s_eq.ignore(pos, end, expected))
+			return false;
 
-	ws.ignore(pos, end);
+		ws.ignore(pos, end);
 
-	if (!s_rparen.ignore(pos, end, expected))
-		return false;
+		if (!storage_p.parse(pos, end, storage, expected))
+			return false;
 
-	ws.ignore(pos, end);
-
-	if (!s_engine.ignore(pos, end, expected))
-		return false;
-
-	ws.ignore(pos, end);
-
-	if (!s_eq.ignore(pos, end, expected))
-		return false;
-
-	ws.ignore(pos, end);
-
-	if (!storage_p.parse(pos, end, storage, expected))
-		return false;
-
-	ws.ignore(pos, end);
+		ws.ignore(pos, end);
+	}
 
 	ASTCreateQuery * query = new ASTCreateQuery(StringRange(begin, pos));
 	node = query;
@@ -168,6 +194,10 @@ bool ParserCreateQuery::parseImpl(Pos & pos, Pos end, ASTPtr & node, String & ex
 	query->table = dynamic_cast<ASTIdentifier &>(*table).name;
 	query->columns = columns;
 	query->storage = storage;
+	if (as_database)
+		query->as_database = dynamic_cast<ASTIdentifier &>(*as_database).name;
+	if (as_table)
+		query->as_table = dynamic_cast<ASTIdentifier &>(*as_table).name;
 
 	query->children.push_back(columns);
 	query->children.push_back(storage);

dbms/src/Storages/StorageFactory.cpp

@@ -0,0 +1,40 @@
+#include <DB/Storages/StorageLog.h>
+#include <DB/Storages/StorageSystemNumbers.h>
+#include <DB/Storages/StorageSystemOne.h>
+#include <DB/Storages/StorageFactory.h>
+
+
+namespace DB
+{
+
+
+StoragePtr StorageFactory::get(
+	const String & name,
+	const String & data_path,
+	const String & table_name,
+	SharedPtr<NamesAndTypes> columns) const
+{
+	if (name == "Log")
+		return new StorageLog(data_path, table_name, columns);
+	else if (name == "SystemNumbers")
+	{
+		if (columns->size() != 1 || columns->begin()->first != "number" || columns->begin()->second->getName() != "UInt64")
+			throw Exception("Storage SystemNumbers only allows one column with name 'number' and type 'UInt64'",
+				ErrorCodes::ILLEGAL_COLUMN);
+
+		return new StorageSystemNumbers(table_name);
+	}
+	else if (name == "SystemOne")
+	{
+		if (columns->size() != 1 || columns->begin()->first != "dummy" || columns->begin()->second->getName() != "UInt8")
+			throw Exception("Storage SystemOne only allows one column with name 'dummy' and type 'UInt8'",
+				ErrorCodes::ILLEGAL_COLUMN);
+
+		return new StorageSystemOne(table_name);
+	}
+	else
+		throw Exception("Unknown storage " + name, ErrorCodes::UNKNOWN_STORAGE);
+}
+
+
+}