ClickHouse/dbms/src/TableFunctions/TableFunctionFactory.cpp

#include <DB/Common/Exception.h>
#include <DB/Interpreters/Context.h>

#include <DB/TableFunctions/TableFunctionMerge.h>
#include <DB/TableFunctions/TableFunctionRemote.h>
#include <DB/TableFunctions/TableFunctionShardByHash.h>

#include <DB/TableFunctions/TableFunctionFactory.h>


namespace DB
{

namespace ErrorCodes
{
	extern const int READONLY;
	extern const int UNKNOWN_FUNCTION;
}


TableFunctionPtr TableFunctionFactory::get(
	const std::string & name,
	const Context & context) const
{
	if (context.getSettings().limits.readonly == 1)		/** For example, for readonly = 2 - allowed. */
		throw Exception("Table functions are forbidden in readonly mode", ErrorCodes::READONLY);

		 if (name == "merge")		return std::make_shared<TableFunctionMerge>();
	else if (name == "remote")		return std::make_shared<TableFunctionRemote>();
	else if (name == "shardByHash")	return std::make_shared<TableFunctionShardByHash>();
	else
		throw Exception("Unknown table function " + name, ErrorCodes::UNKNOWN_FUNCTION);
}

}