ClickHouse/src/Functions/identity.cpp
Li Yin 4088c0a7f3 Automated function registration
Automated register all functions with below naming convention by
iterating through the symbols:
void DB::registerXXX(DB::FunctionFactory &)
2022-07-29 15:39:50 +08:00

43 lines
1.0 KiB
C++

#include <Functions/IFunction.h>
#include <Functions/FunctionFactory.h>
namespace DB
{
namespace
{
class FunctionIdentity : public IFunction
{
public:
static constexpr auto name = "identity";
static FunctionPtr create(ContextPtr)
{
return std::make_shared<FunctionIdentity>();
}
String getName() const override { return name; }
size_t getNumberOfArguments() const override { return 1; }
bool isSuitableForConstantFolding() const override { return false; }
bool isSuitableForShortCircuitArgumentsExecution(const DataTypesWithConstInfo & /*arguments*/) const override { return false; }
DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
{
return arguments.front();
}
ColumnPtr executeImpl(const ColumnsWithTypeAndName & arguments, const DataTypePtr &, size_t /*input_rows_count*/) const override
{
return arguments.front().column;
}
};
}
REGISTER_FUNCTION(Identity)
{
factory.registerFunction<FunctionIdentity>();
}
}