ClickHouse/src/Functions/intExp10.cpp

68 lines
1.9 KiB
C++

#include <Functions/FunctionFactory.h>
#include <Functions/FunctionUnaryArithmetic.h>
#include <Common/FieldVisitorConvertToNumber.h>
#include <Common/intExp.h>
namespace DB
{
namespace ErrorCodes
{
extern const int NOT_IMPLEMENTED;
}
namespace
{
template <typename A>
struct IntExp10Impl
{
using ResultType = UInt64;
static constexpr const bool allow_fixed_string = false;
static const constexpr bool allow_string_integer = false;
static inline ResultType apply([[maybe_unused]] A a)
{
if constexpr (is_big_int_v<A> || std::is_same_v<A, Decimal256>)
throw DB::Exception("IntExp10 is not implemented for big integers", ErrorCodes::NOT_IMPLEMENTED);
else
return intExp10(static_cast<int>(a));
}
#if USE_EMBEDDED_COMPILER
static constexpr bool compilable = false; /// library function
#endif
};
struct NameIntExp10 { static constexpr auto name = "intExp10"; };
/// Assumed to be injective for the purpose of query optimization, but in fact it is not injective because of possible overflow.
using FunctionIntExp10 = FunctionUnaryArithmetic<IntExp10Impl, NameIntExp10, true>;
}
template <> struct FunctionUnaryArithmeticMonotonicity<NameIntExp10>
{
static bool has() { return true; }
static IFunction::Monotonicity get(const Field & left, const Field & right)
{
Float64 left_float = left.isNull()
? -std::numeric_limits<Float64>::infinity()
: applyVisitor(FieldVisitorConvertToNumber<Float64>(), left);
Float64 right_float = right.isNull()
? std::numeric_limits<Float64>::infinity()
: applyVisitor(FieldVisitorConvertToNumber<Float64>(), right);
if (left_float < 0 || right_float > 19)
return {};
return { .is_monotonic = true, .is_strict = true };
}
};
REGISTER_FUNCTION(IntExp10)
{
factory.registerFunction<FunctionIntExp10>();
}
}