Preparations [#METR-20307].

dbms/include/DB/Core/Block.h

@@ -29,7 +29,7 @@ class Context;
 class Block
 {
 private:
-	using Container = std::vector<ColumnWithTypeAndName>;
+	using Container = ColumnsWithTypeAndName;
 	using IndexByName = std::map<String, size_t>;
 
 	Container data;
@@ -39,15 +39,8 @@ public:
 	BlockInfo info;
 
 	Block() = default;
-	Block(std::initializer_list<ColumnWithTypeAndName> il) : data{il}
-	{
-		size_t i = 0;
-		for (const auto & elem : il)
-		{
-			index_by_name[elem.name] = i;
-			++i;
-		}
-	}
+	Block(std::initializer_list<ColumnWithTypeAndName> il);
+	Block(const ColumnsWithTypeAndName & data_);
 
 	/// вставить столбец в заданную позицию
 	void insert(size_t position, const ColumnWithTypeAndName & elem);
@@ -128,6 +121,7 @@ public:
 
 private:
 	void eraseImpl(size_t position);
+	void initializeIndexByName();
 };
 
 using Blocks = std::vector<Block>;

dbms/include/DB/DataTypes/FieldToDataType.h

@@ -19,12 +19,12 @@ namespace DB
 class FieldToDataType : public StaticVisitor<DataTypePtr>
 {
 public:
-	DataTypePtr operator() (Null 	& x) const
+	DataTypePtr operator() (const Null & x) const
 	{
 		return std::make_shared<DataTypeNull>();
 	}
 
-	DataTypePtr operator() (UInt64 	& x) const
+	DataTypePtr operator() (const UInt64 & x) const
 	{
 		if (x <= std::numeric_limits<UInt8>::max())		return std::make_shared<DataTypeUInt8>();
 		if (x <= std::numeric_limits<UInt16>::max())	return std::make_shared<DataTypeUInt16>();
@@ -32,7 +32,7 @@ public:
 		return std::make_shared<DataTypeUInt64>();
 	}
 
-	DataTypePtr operator() (Int64 	& x) const
+	DataTypePtr operator() (const Int64 & x) const
 	{
 		if (x <= std::numeric_limits<Int8>::max() && x >= std::numeric_limits<Int8>::min())		return std::make_shared<DataTypeInt8>();
 		if (x <= std::numeric_limits<Int16>::max() && x >= std::numeric_limits<Int16>::min())	return std::make_shared<DataTypeInt16>();
@@ -40,19 +40,19 @@ public:
 		return std::make_shared<DataTypeInt64>();
 	}
 
-	DataTypePtr operator() (Float64 & x) const
+	DataTypePtr operator() (const Float64 & x) const
 	{
 		return std::make_shared<DataTypeFloat64>();
 	}
 
-	DataTypePtr operator() (String 	& x) const
+	DataTypePtr operator() (const String & x) const
 	{
 		return std::make_shared<DataTypeString>();
 	}
 
-	DataTypePtr operator() (Array 	& x) const;
+	DataTypePtr operator() (const Array & x) const;
 
-	DataTypePtr operator() (Tuple 	& x) const;
+	DataTypePtr operator() (const Tuple & x) const;
 };
 
 }

dbms/src/Core/Block.cpp

@@ -89,6 +89,25 @@ void Block::addDefaults(const NamesAndTypesList & required_columns)
 }
 
 
+Block::Block(std::initializer_list<ColumnWithTypeAndName> il) : data{il}
+{
+	initializeIndexByName();
+}
+
+
+Block::Block(const ColumnsWithTypeAndName & data_) : data{data_}
+{
+	initializeIndexByName();
+}
+
+
+void Block::initializeIndexByName()
+{
+	for (size_t i = 0, size = data.size(); i < size; ++i)
+		index_by_name[data[i].name] = i;
+}
+
+
 void Block::insert(size_t position, const ColumnWithTypeAndName & elem)
 {
 	if (position > data.size())
@@ -359,7 +378,7 @@ Block Block::sortColumns() const
 
 ColumnsWithTypeAndName Block::getColumns() const
 {
-	return ColumnsWithTypeAndName(data.begin(), data.end());
+	return data;
 }
 
 

dbms/src/DataTypes/FieldToDataType.cpp

@@ -17,9 +17,9 @@ namespace ErrorCodes
 
 
 template <typename T>
-static void convertArrayToCommonType(Array & arr)
+static void convertArrayToCommonType(const Array & arr)
 {
-	for (auto & elem : arr)
+	for (const auto & elem : arr)
 	{
 		if (!elem.isNull())
 			elem = apply_visitor(FieldVisitorConvertToNumber<T>(), elem);
@@ -27,7 +27,7 @@ static void convertArrayToCommonType(Array & arr)
 }
 
 
-DataTypePtr FieldToDataType::operator() (Array & x) const
+DataTypePtr FieldToDataType::operator() (const Array & x) const
 {
 	if (x.empty())
 		throw Exception("Cannot infer type of empty array", ErrorCodes::EMPTY_DATA_PASSED);
@@ -207,16 +207,16 @@ DataTypePtr FieldToDataType::operator() (Array & x) const
 }
 
 
-DataTypePtr FieldToDataType::operator() (Tuple & x) const
+DataTypePtr FieldToDataType::operator() (const Tuple & x) const
 {
-	auto & tuple = static_cast<TupleBackend &>(x);
+	const auto & tuple = static_cast<const TupleBackend &>(x);
 	if (tuple.empty())
 		throw Exception("Cannot infer type of an empty tuple", ErrorCodes::EMPTY_DATA_PASSED);
 
 	DataTypes element_types;
 	element_types.reserve(ext::size(tuple));
 
-	for (auto & element : tuple)
+	for (const auto & element : tuple)
 		element_types.push_back(apply_visitor(FieldToDataType{}, element));
 
 	return std::make_shared<DataTypeTuple>(element_types);