mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-12-15 02:41:59 +00:00
78 lines
2.3 KiB
C++
78 lines
2.3 KiB
C++
#pragma once
|
|
#include <DataTypes/DataTypeString.h>
|
|
#include <Columns/ColumnString.h>
|
|
#include <Columns/ColumnFixedString.h>
|
|
#include <Functions/FunctionHelpers.h>
|
|
#include <Functions/IFunctionImpl.h>
|
|
|
|
|
|
namespace DB
|
|
{
|
|
|
|
namespace ErrorCodes
|
|
{
|
|
extern const int ILLEGAL_COLUMN;
|
|
extern const int ILLEGAL_TYPE_OF_ARGUMENT;
|
|
}
|
|
|
|
|
|
template <typename Impl, typename Name, bool is_injective = false>
|
|
class FunctionStringToString : public IFunction
|
|
{
|
|
public:
|
|
static constexpr auto name = Name::name;
|
|
static FunctionPtr create(const Context &)
|
|
{
|
|
return std::make_shared<FunctionStringToString>();
|
|
}
|
|
|
|
String getName() const override
|
|
{
|
|
return name;
|
|
}
|
|
|
|
size_t getNumberOfArguments() const override
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
bool isInjective(const ColumnsWithTypeAndName &) const override
|
|
{
|
|
return is_injective;
|
|
}
|
|
|
|
DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
|
|
{
|
|
if (!isStringOrFixedString(arguments[0]))
|
|
throw Exception(
|
|
"Illegal type " + arguments[0]->getName() + " of argument of function " + getName(), ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT);
|
|
|
|
return arguments[0];
|
|
}
|
|
|
|
bool useDefaultImplementationForConstants() const override { return true; }
|
|
|
|
void executeImpl(ColumnsWithTypeAndName & block, const ColumnNumbers & arguments, size_t result, size_t /*input_rows_count*/) const override
|
|
{
|
|
const ColumnPtr column = block[arguments[0]].column;
|
|
if (const ColumnString * col = checkAndGetColumn<ColumnString>(column.get()))
|
|
{
|
|
auto col_res = ColumnString::create();
|
|
Impl::vector(col->getChars(), col->getOffsets(), col_res->getChars(), col_res->getOffsets());
|
|
block[result].column = std::move(col_res);
|
|
}
|
|
else if (const ColumnFixedString * col_fixed = checkAndGetColumn<ColumnFixedString>(column.get()))
|
|
{
|
|
auto col_res = ColumnFixedString::create(col_fixed->getN());
|
|
Impl::vectorFixed(col_fixed->getChars(), col_fixed->getN(), col_res->getChars());
|
|
block[result].column = std::move(col_res);
|
|
}
|
|
else
|
|
throw Exception(
|
|
"Illegal column " + block[arguments[0]].column->getName() + " of argument of function " + getName(),
|
|
ErrorCodes::ILLEGAL_COLUMN);
|
|
}
|
|
};
|
|
|
|
}
|