mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-11-14 03:25:15 +00:00
109 lines
2.9 KiB
C++
109 lines
2.9 KiB
C++
#pragma once
|
||
|
||
#include <DB/DataTypes/DataTypeAggregateFunction.h>
|
||
#include <DB/AggregateFunctions/IAggregateFunction.h>
|
||
#include <DB/Columns/ColumnAggregateFunction.h>
|
||
|
||
|
||
namespace DB
|
||
{
|
||
|
||
|
||
/** Не агрегатная функция, а адаптер агрегатных функций,
|
||
* Агрегатные функции с суффиксом Merge принимают в качестве аргумента DataTypeAggregateFunction
|
||
* (состояние агрегатной функции, полученное ранее с помощью применения агрегатной функции с суффиксом State)
|
||
* и объединяют их при агрегации.
|
||
*/
|
||
|
||
class AggregateFunctionMerge final : public IAggregateFunction
|
||
{
|
||
private:
|
||
AggregateFunctionPtr nested_func_owner;
|
||
IAggregateFunction * nested_func;
|
||
|
||
public:
|
||
AggregateFunctionMerge(AggregateFunctionPtr nested_) : nested_func_owner(nested_), nested_func(nested_func_owner.get()) {}
|
||
|
||
String getName() const
|
||
{
|
||
return nested_func->getName() + "Merge";
|
||
}
|
||
|
||
DataTypePtr getReturnType() const
|
||
{
|
||
return nested_func->getReturnType();
|
||
}
|
||
|
||
void setArguments(const DataTypes & arguments)
|
||
{
|
||
if (arguments.size() != 1)
|
||
throw Exception("Passed " + toString(arguments.size()) + " arguments to unary aggregate function " + this->getName(),
|
||
ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);
|
||
|
||
const DataTypeAggregateFunction * data_type = typeid_cast<const DataTypeAggregateFunction *>(&*arguments[0]);
|
||
|
||
if (!data_type || data_type->getFunctionName() != nested_func->getName())
|
||
throw Exception("Illegal type " + arguments[0]->getName() + " of argument for aggregate function " + getName(),
|
||
ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
|
||
|
||
nested_func->setArguments(data_type->getArgumentsDataTypes());
|
||
}
|
||
|
||
void setParameters(const Array & params)
|
||
{
|
||
nested_func->setParameters(params);
|
||
}
|
||
|
||
void create(AggregateDataPtr place) const
|
||
{
|
||
nested_func->create(place);
|
||
}
|
||
|
||
void destroy(AggregateDataPtr place) const noexcept
|
||
{
|
||
nested_func->destroy(place);
|
||
}
|
||
|
||
bool hasTrivialDestructor() const
|
||
{
|
||
return nested_func->hasTrivialDestructor();
|
||
}
|
||
|
||
size_t sizeOfData() const
|
||
{
|
||
return nested_func->sizeOfData();
|
||
}
|
||
|
||
size_t alignOfData() const
|
||
{
|
||
return nested_func->alignOfData();
|
||
}
|
||
|
||
void add(AggregateDataPtr place, const IColumn ** columns, size_t row_num) const
|
||
{
|
||
nested_func->merge(place, static_cast<const ColumnAggregateFunction &>(*columns[0]).getData()[row_num]);
|
||
}
|
||
|
||
void merge(AggregateDataPtr place, ConstAggregateDataPtr rhs) const
|
||
{
|
||
nested_func->merge(place, rhs);
|
||
}
|
||
|
||
void serialize(ConstAggregateDataPtr place, WriteBuffer & buf) const
|
||
{
|
||
nested_func->serialize(place, buf);
|
||
}
|
||
|
||
void deserializeMerge(AggregateDataPtr place, ReadBuffer & buf) const
|
||
{
|
||
nested_func->deserializeMerge(place, buf);
|
||
}
|
||
|
||
void insertResultInto(ConstAggregateDataPtr place, IColumn & to) const
|
||
{
|
||
nested_func->insertResultInto(place, to);
|
||
}
|
||
};
|
||
|
||
}
|