ClickHouse/dbms/src/Functions/FunctionStringOrArrayToT.h
2019-01-04 15:10:00 +03:00

102 lines
3.4 KiB
C++

#include <DataTypes/DataTypeString.h>
#include <DataTypes/DataTypesNumber.h>
#include <Functions/IFunction.h>
#include <Functions/FunctionHelpers.h>
#include <Columns/ColumnVector.h>
#include <Columns/ColumnString.h>
#include <Columns/ColumnFixedString.h>
#include <Columns/ColumnArray.h>
namespace DB
{
namespace ErrorCodes
{
extern const int ILLEGAL_COLUMN;
extern const int ILLEGAL_TYPE_OF_ARGUMENT;
}
template <typename Impl, typename Name, typename ResultType>
class FunctionStringOrArrayToT : public IFunction
{
public:
static constexpr auto name = Name::name;
static FunctionPtr create(const Context &)
{
return std::make_shared<FunctionStringOrArrayToT>();
}
String getName() const override
{
return name;
}
size_t getNumberOfArguments() const override
{
return 1;
}
DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
{
if (!isStringOrFixedString(arguments[0])
&& !isArray(arguments[0]))
throw Exception("Illegal type " + arguments[0]->getName() + " of argument of function " + getName(), ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
return std::make_shared<DataTypeNumber<ResultType>>();
}
bool useDefaultImplementationForConstants() const override { return true; }
void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result, size_t /*input_rows_count*/) override
{
const ColumnPtr column = block.getByPosition(arguments[0]).column;
if (const ColumnString * col = checkAndGetColumn<ColumnString>(column.get()))
{
auto col_res = ColumnVector<ResultType>::create();
typename ColumnVector<ResultType>::Container & vec_res = col_res->getData();
vec_res.resize(col->size());
Impl::vector(col->getChars(), col->getOffsets(), vec_res);
block.getByPosition(result).column = std::move(col_res);
}
else if (const ColumnFixedString * col_fixed = checkAndGetColumn<ColumnFixedString>(column.get()))
{
if (Impl::is_fixed_to_constant)
{
ResultType res = 0;
Impl::vector_fixed_to_constant(col_fixed->getChars(), col_fixed->getN(), res);
block.getByPosition(result).column = block.getByPosition(result).type->createColumnConst(col_fixed->size(), toField(res));
}
else
{
auto col_res = ColumnVector<ResultType>::create();
typename ColumnVector<ResultType>::Container & vec_res = col_res->getData();
vec_res.resize(col_fixed->size());
Impl::vector_fixed_to_vector(col_fixed->getChars(), col_fixed->getN(), vec_res);
block.getByPosition(result).column = std::move(col_res);
}
}
else if (const ColumnArray * col_arr = checkAndGetColumn<ColumnArray>(column.get()))
{
auto col_res = ColumnVector<ResultType>::create();
typename ColumnVector<ResultType>::Container & vec_res = col_res->getData();
vec_res.resize(col_arr->size());
Impl::array(col_arr->getOffsets(), vec_res);
block.getByPosition(result).column = std::move(col_res);
}
else
throw Exception("Illegal column " + block.getByPosition(arguments[0]).column->getName() + " of argument of function " + getName(),
ErrorCodes::ILLEGAL_COLUMN);
}
};
}