be/src/vec/aggregate_functions/aggregate_function_bool_union.h

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// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
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// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

#pragma once

#include "runtime/define_primitive_type.h"
#include "runtime/primitive_type.h"
#include "vec/aggregate_functions/aggregate_function.h"
#include "vec/aggregate_functions/aggregate_function_bit.h"
#include "vec/columns/column_nullable.h"
#include "vec/columns/column_vector.h"
#include "vec/common/assert_cast.h"
#include "vec/core/types.h"
#include "vec/data_types/data_type.h"
#include "vec/data_types/data_type_nullable.h"
#include "vec/data_types/data_type_number.h"

namespace doris::vectorized {
#include "common/compile_check_begin.h"

struct AggregateFunctionBoolXorData {
    static constexpr auto name = "bool_xor";

    void add(bool x) {
        if (x && _st < 2) {
            ++_st;
        }
    }

    void merge(const AggregateFunctionBoolXorData& rhs) {
        if (_st == 0) {
            _st = rhs._st;
        } else if (_st == 1) {
            _st = (rhs._st > 0) ? 2 : 1;
        }
    }

    void write(BufferWritable& buf) const { buf.write_binary(_st); }

    void read(BufferReadable& buf) { buf.read_binary(_st); }

    void reset() { _st = 0; }

    bool get() const { return _st == 1; }

private:
    // represents the current XOR state
    // '0': there are no true values currently
    // '1': exactly one true value has appeared
    // '2': two true values have already appeared and will not change thereafter
    uint8_t _st = 0;
};

template <typename BoolFunc>
class AggregateFuntionBoolUnion final
        : public IAggregateFunctionDataHelper<BoolFunc, AggregateFuntionBoolUnion<BoolFunc>>,
          NullableAggregateFunction,
          UnaryExpression {
public:
    explicit AggregateFuntionBoolUnion(const DataTypes& argument_types_)
            : IAggregateFunctionDataHelper<BoolFunc, AggregateFuntionBoolUnion<BoolFunc>>(
                      argument_types_) {}

    String get_name() const override { return BoolFunc::name; }

    DataTypePtr get_return_type() const override { return std::make_shared<DataTypeBool>(); }

    void add(AggregateDataPtr __restrict place, const IColumn** columns, ssize_t row_num,
             Arena&) const override {
        this->data(place).add(
                assert_cast<const ColumnUInt8&, TypeCheckOnRelease::DISABLE>(*columns[0])
                        .get_element(row_num));
    }

    void reset(AggregateDataPtr __restrict place) const override { this->data(place).reset(); }

    void merge(AggregateDataPtr __restrict place, ConstAggregateDataPtr rhs,
               Arena&) const override {
        this->data(place).merge(this->data(rhs));
    }

    void serialize(ConstAggregateDataPtr __restrict place, BufferWritable& buf) const override {
        this->data(place).write(buf);
    }

    void deserialize(AggregateDataPtr __restrict place, BufferReadable& buf,
                     Arena&) const override {
        this->data(place).read(buf);
    }

    void insert_result_into(ConstAggregateDataPtr __restrict place, IColumn& to) const override {
        assert_cast<ColumnUInt8&>(to).insert_value(this->data(place).get());
    }
};
} // namespace doris::vectorized

#include "common/compile_check_end.h"