1 | #pragma once |
2 | |
3 | #include <IO/ReadHelpers.h> |
4 | #include <IO/WriteHelpers.h> |
5 | |
6 | #include <Columns/ColumnsNumber.h> |
7 | #include <DataTypes/DataTypesDecimal.h> |
8 | #include <DataTypes/DataTypesNumber.h> |
9 | |
10 | #include <AggregateFunctions/IAggregateFunction.h> |
11 | |
12 | |
13 | namespace DB |
14 | { |
15 | namespace ErrorCodes |
16 | { |
17 | extern const int LOGICAL_ERROR; |
18 | } |
19 | |
20 | template <typename T, typename Denominator> |
21 | struct AggregateFunctionAvgData |
22 | { |
23 | T numerator = 0; |
24 | Denominator denominator = 0; |
25 | |
26 | template <typename ResultT> |
27 | ResultT NO_SANITIZE_UNDEFINED result() const |
28 | { |
29 | if constexpr (std::is_floating_point_v<ResultT>) |
30 | if constexpr (std::numeric_limits<ResultT>::is_iec559) |
31 | return static_cast<ResultT>(numerator) / denominator; /// allow division by zero |
32 | |
33 | if (denominator == 0) |
34 | return static_cast<ResultT>(0); |
35 | return static_cast<ResultT>(numerator / denominator); |
36 | } |
37 | }; |
38 | |
39 | /// Calculates arithmetic mean of numbers. |
40 | template <typename T, typename Data, typename Derived> |
41 | class AggregateFunctionAvgBase : public IAggregateFunctionDataHelper<Data, Derived> |
42 | { |
43 | public: |
44 | using ResultType = std::conditional_t<IsDecimalNumber<T>, T, Float64>; |
45 | using ResultDataType = std::conditional_t<IsDecimalNumber<T>, DataTypeDecimal<T>, DataTypeNumber<Float64>>; |
46 | using ColVecType = std::conditional_t<IsDecimalNumber<T>, ColumnDecimal<T>, ColumnVector<T>>; |
47 | using ColVecResult = std::conditional_t<IsDecimalNumber<T>, ColumnDecimal<T>, ColumnVector<Float64>>; |
48 | |
49 | /// ctor for native types |
50 | AggregateFunctionAvgBase(const DataTypes & argument_types_) : IAggregateFunctionDataHelper<Data, Derived>(argument_types_, {}), scale(0) {} |
51 | |
52 | /// ctor for Decimals |
53 | AggregateFunctionAvgBase(const IDataType & data_type, const DataTypes & argument_types_) |
54 | : IAggregateFunctionDataHelper<Data, Derived>(argument_types_, {}), scale(getDecimalScale(data_type)) |
55 | { |
56 | } |
57 | |
58 | DataTypePtr getReturnType() const override |
59 | { |
60 | if constexpr (IsDecimalNumber<T>) |
61 | return std::make_shared<ResultDataType>(ResultDataType::maxPrecision(), scale); |
62 | else |
63 | return std::make_shared<ResultDataType>(); |
64 | } |
65 | |
66 | void merge(AggregateDataPtr place, ConstAggregateDataPtr rhs, Arena *) const override |
67 | { |
68 | this->data(place).numerator += this->data(rhs).numerator; |
69 | this->data(place).denominator += this->data(rhs).denominator; |
70 | } |
71 | |
72 | void serialize(ConstAggregateDataPtr place, WriteBuffer & buf) const override |
73 | { |
74 | writeBinary(this->data(place).numerator, buf); |
75 | writeVarUInt(this->data(place).denominator, buf); |
76 | } |
77 | |
78 | void deserialize(AggregateDataPtr place, ReadBuffer & buf, Arena *) const override |
79 | { |
80 | readBinary(this->data(place).numerator, buf); |
81 | readVarUInt(this->data(place).denominator, buf); |
82 | } |
83 | |
84 | void insertResultInto(ConstAggregateDataPtr place, IColumn & to) const override |
85 | { |
86 | auto & column = static_cast<ColVecResult &>(to); |
87 | column.getData().push_back(this->data(place).template result<ResultType>()); |
88 | } |
89 | |
90 | protected: |
91 | UInt32 scale; |
92 | }; |
93 | |
94 | template <typename T, typename Data> |
95 | class AggregateFunctionAvg final : public AggregateFunctionAvgBase<T, Data, AggregateFunctionAvg<T, Data>> |
96 | { |
97 | public: |
98 | using AggregateFunctionAvgBase<T, Data, AggregateFunctionAvg<T, Data>>::AggregateFunctionAvgBase; |
99 | |
100 | using ColVecType = std::conditional_t<IsDecimalNumber<T>, ColumnDecimal<T>, ColumnVector<T>>; |
101 | void add(AggregateDataPtr place, const IColumn ** columns, size_t row_num, Arena *) const override |
102 | { |
103 | const auto & column = static_cast<const ColVecType &>(*columns[0]); |
104 | this->data(place).numerator += column.getData()[row_num]; |
105 | this->data(place).denominator += 1; |
106 | } |
107 | |
108 | String getName() const override { return "avg" ; } |
109 | }; |
110 | |
111 | } |
112 | |