ClickHouse/dbms/src/Functions/FunctionHelpers.h

295 lines
10 KiB
C++

#pragma once
#include <Common/typeid_cast.h>
#include <DataTypes/IDataType.h>
#include <Columns/IColumn.h>
#include <Columns/ColumnConst.h>
#include <Core/Block.h>
#include <Core/ColumnNumbers.h>
namespace DB
{
/// Methods, that helps dispatching over real column types.
template <typename Type>
const Type * checkAndGetDataType(const IDataType * data_type)
{
return typeid_cast<const Type *>(data_type);
}
template <typename Type>
bool checkDataType(const IDataType * data_type)
{
return checkAndGetDataType<Type>(data_type);
}
template <typename Type>
const Type * checkAndGetColumn(const IColumn * column)
{
return typeid_cast<const Type *>(column);
}
template <typename Type>
bool checkColumn(const IColumn * column)
{
return checkAndGetColumn<Type>(column);
}
template <typename Type>
const ColumnConst * checkAndGetColumnConst(const IColumn * column)
{
if (!column || !column->isColumnConst())
return {};
const ColumnConst * res = static_cast<const ColumnConst *>(column);
if (!checkColumn<Type>(&res->getDataColumn()))
return {};
return res;
}
template <typename Type>
const Type * checkAndGetColumnConstData(const IColumn * column)
{
const ColumnConst * res = checkAndGetColumnConst<Type>(column);
if (!res)
return {};
return static_cast<const Type *>(&res->getDataColumn());
}
template <typename Type>
bool checkColumnConst(const IColumn * column)
{
return checkAndGetColumnConst<Type>(column);
}
/// Returns non-nullptr if column is ColumnConst with ColumnString or ColumnFixedString inside.
const ColumnConst * checkAndGetColumnConstStringOrFixedString(const IColumn * column);
/// Transform anything to Field.
template <typename T>
inline Field toField(const T & x)
{
return Field(typename NearestFieldType<T>::Type(x));
}
Columns convertConstTupleToConstantElements(const ColumnConst & column);
/// Returns the copy of a given block in which each column specified in
/// the "arguments" parameter is replaced with its respective nested
/// column if it is nullable.
Block createBlockWithNestedColumns(const Block & block, const ColumnNumbers & args);
/// Similar function as above. Additionally transform the result type if needed.
Block createBlockWithNestedColumns(const Block & block, const ColumnNumbers & args, size_t result);
template <typename T, typename U>
struct TypePair
{
using LeftType = T;
using RightType = U;
};
template <typename T, bool _int, bool _dec, bool _float, typename F>
bool callOnBasicType(TypeIndex number, F && f)
{
if constexpr (_int)
{
switch (number)
{
case TypeIndex::UInt8: return f(TypePair<T, UInt8>());
case TypeIndex::UInt16: return f(TypePair<T, UInt16>());
case TypeIndex::UInt32: return f(TypePair<T, UInt32>());
case TypeIndex::UInt64: return f(TypePair<T, UInt64>());
//case TypeIndex::UInt128>: return f(TypePair<T, UInt128>());
case TypeIndex::Int8: return f(TypePair<T, Int8>());
case TypeIndex::Int16: return f(TypePair<T, Int16>());
case TypeIndex::Int32: return f(TypePair<T, Int32>());
case TypeIndex::Int64: return f(TypePair<T, Int64>());
case TypeIndex::Int128: return f(TypePair<T, Int128>());
default:
break;
}
}
if constexpr (_dec)
{
switch (number)
{
case TypeIndex::Decimal32: return f(TypePair<T, Decimal32>());
case TypeIndex::Decimal64: return f(TypePair<T, Decimal64>());
case TypeIndex::Decimal128: return f(TypePair<T, Decimal128>());
default:
break;
}
}
if constexpr (_float)
{
switch (number)
{
case TypeIndex::Float32: return f(TypePair<T, Float32>());
case TypeIndex::Float64: return f(TypePair<T, Float64>());
default:
break;
}
}
return false;
}
/// Unroll template using TypeIndex
template <typename F, bool _int = true, bool _dec = true, bool _float = false>
inline bool callOnBasicTypes(TypeIndex type_num1, TypeIndex type_num2, F && f)
{
if constexpr (_int)
{
switch (type_num1)
{
case TypeIndex::UInt8: return callOnBasicType<UInt8, _int, _dec, _float>(type_num2, std::forward<F>(f));
case TypeIndex::UInt16: return callOnBasicType<UInt16, _int, _dec, _float>(type_num2, std::forward<F>(f));
case TypeIndex::UInt32: return callOnBasicType<UInt32, _int, _dec, _float>(type_num2, std::forward<F>(f));
case TypeIndex::UInt64: return callOnBasicType<UInt64, _int, _dec, _float>(type_num2, std::forward<F>(f));
//case TypeIndex::UInt128: return callOnBasicType<UInt128, _int, _dec, _float>(type_num2, std::forward<F>(f));
case TypeIndex::Int8: return callOnBasicType<Int8, _int, _dec, _float>(type_num2, std::forward<F>(f));
case TypeIndex::Int16: return callOnBasicType<Int16, _int, _dec, _float>(type_num2, std::forward<F>(f));
case TypeIndex::Int32: return callOnBasicType<Int32, _int, _dec, _float>(type_num2, std::forward<F>(f));
case TypeIndex::Int64: return callOnBasicType<Int64, _int, _dec, _float>(type_num2, std::forward<F>(f));
case TypeIndex::Int128: return callOnBasicType<Int128, _int, _dec, _float>(type_num2, std::forward<F>(f));
default:
break;
}
}
if constexpr (_dec)
{
switch (type_num1)
{
case TypeIndex::Decimal32: return callOnBasicType<Decimal32, _int, _dec, _float>(type_num2, std::forward<F>(f));
case TypeIndex::Decimal64: return callOnBasicType<Decimal64, _int, _dec, _float>(type_num2, std::forward<F>(f));
case TypeIndex::Decimal128: return callOnBasicType<Decimal128, _int, _dec, _float>(type_num2, std::forward<F>(f));
default:
break;
}
}
if constexpr (_float)
{
switch (type_num1)
{
case TypeIndex::Float32: return callOnBasicType<Float32, _int, _dec, _float>(type_num2, std::forward<F>(f));
case TypeIndex::Float64: return callOnBasicType<Float64, _int, _dec, _float>(type_num2, std::forward<F>(f));
default:
break;
}
}
return false;
}
class DataTypeDate;
class DataTypeDateTime;
class DataTypeString;
class DataTypeFixedString;
class DataTypeUUID;
template <typename T> class DataTypeEnum;
template <typename T> class DataTypeNumber;
template <typename T> class DataTypeDecimal;
template <typename T, typename F>
bool callOnDataTypeAndIndex(TypeIndex number, F && f)
{
switch (number)
{
case TypeIndex::UInt8: return f(TypePair<T, DataTypeNumber<UInt8>>());
case TypeIndex::UInt16: return f(TypePair<T, DataTypeNumber<UInt16>>());
case TypeIndex::UInt32: return f(TypePair<T, DataTypeNumber<UInt32>>());
case TypeIndex::UInt64: return f(TypePair<T, DataTypeNumber<UInt64>>());
case TypeIndex::Int8: return f(TypePair<T, DataTypeNumber<Int8>>());
case TypeIndex::Int16: return f(TypePair<T, DataTypeNumber<Int16>>());
case TypeIndex::Int32: return f(TypePair<T, DataTypeNumber<Int32>>());
case TypeIndex::Int64: return f(TypePair<T, DataTypeNumber<Int64>>());
case TypeIndex::Float32: return f(TypePair<T, DataTypeNumber<Float32>>());
case TypeIndex::Float64: return f(TypePair<T, DataTypeNumber<Float64>>());
case TypeIndex::Decimal32: return f(TypePair<T, DataTypeDecimal<Decimal32>>());
case TypeIndex::Decimal64: return f(TypePair<T, DataTypeDecimal<Decimal64>>());
case TypeIndex::Decimal128: return f(TypePair<T, DataTypeDecimal<Decimal128>>());
case TypeIndex::Date: return f(TypePair<T, DataTypeDate>());
case TypeIndex::DateTime: return f(TypePair<T, DataTypeDateTime>());
case TypeIndex::String: return f(TypePair<T, DataTypeString>());
case TypeIndex::FixedString: return f(TypePair<T, DataTypeFixedString>());
case TypeIndex::Enum8: return f(TypePair<T, DataTypeEnum<Int8>>());
case TypeIndex::Enum16: return f(TypePair<T, DataTypeEnum<Int16>>());
case TypeIndex::UUID: return f(TypePair<T, DataTypeUUID>());
default:
break;
}
return false;
}
template <typename T, typename F>
bool callOnIndexAndDataType(TypeIndex number, F && f)
{
switch (number)
{
case TypeIndex::UInt8: return f(TypePair<DataTypeNumber<UInt8>, T>());
case TypeIndex::UInt16: return f(TypePair<DataTypeNumber<UInt16>, T>());
case TypeIndex::UInt32: return f(TypePair<DataTypeNumber<UInt32>, T>());
case TypeIndex::UInt64: return f(TypePair<DataTypeNumber<UInt64>, T>());
case TypeIndex::Int8: return f(TypePair<DataTypeNumber<Int8>, T>());
case TypeIndex::Int16: return f(TypePair<DataTypeNumber<Int16>, T>());
case TypeIndex::Int32: return f(TypePair<DataTypeNumber<Int32>, T>());
case TypeIndex::Int64: return f(TypePair<DataTypeNumber<Int64>, T>());
case TypeIndex::Float32: return f(TypePair<DataTypeNumber<Float32>, T>());
case TypeIndex::Float64: return f(TypePair<DataTypeNumber<Float64>, T>());
case TypeIndex::Decimal32: return f(TypePair<DataTypeDecimal<Decimal32>, T>());
case TypeIndex::Decimal64: return f(TypePair<DataTypeDecimal<Decimal64>, T>());
case TypeIndex::Decimal128: return f(TypePair<DataTypeDecimal<Decimal128>, T>());
case TypeIndex::Date: return f(TypePair<DataTypeDate, T>());
case TypeIndex::DateTime: return f(TypePair<DataTypeDateTime, T>());
case TypeIndex::String: return f(TypePair<DataTypeString, T>());
case TypeIndex::FixedString: return f(TypePair<DataTypeFixedString, T>());
case TypeIndex::Enum8: return f(TypePair<DataTypeEnum<Int8>, T>());
case TypeIndex::Enum16: return f(TypePair<DataTypeEnum<Int16>, T>());
case TypeIndex::UUID: return f(TypePair<DataTypeUUID, T>());
default:
break;
}
return false;
}
}