ClickHouse

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#include <Functions/FunctionFactory.h>
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#include <Functions/FunctionBinaryArithmetic.h>
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#include <DataTypes/NumberTraits.h>
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namespace DB
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{
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namespace ErrorCodes
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{
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    extern const int BAD_ARGUMENTS;
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}
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namespace
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{
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/// Working with UInt8: last bit = can be true, previous = can be false (Like src/Storages/MergeTree/BoolMask.h).
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/// This function provides "AND" operation for BoolMasks.
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/// Returns: "can be true" = A."can be true" AND B."can be true"
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///          "can be false" = A."can be false" OR B."can be false"
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template <typename A, typename B>
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struct BitBoolMaskAndImpl
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{
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    using ResultType = UInt8;
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    static const constexpr bool allow_fixed_string = false;
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    static const constexpr bool allow_string_integer = false;
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    template <typename Result = ResultType>
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    static inline Result apply([[maybe_unused]] A left, [[maybe_unused]] B right)
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    {
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        // Should be a logical error, but this function is callable from SQL.
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        // Need to investigate this.
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        if constexpr (!std::is_same_v<A, ResultType> || !std::is_same_v<B, ResultType>)
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            throw DB::Exception(ErrorCodes::BAD_ARGUMENTS, "It's a bug! Only UInt8 type is supported by __bitBoolMaskAnd.");
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        auto left_bits = littleBits<A>(left);
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        auto right_bits = littleBits<B>(right);
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        return static_cast<ResultType>((left_bits & right_bits & 1) | ((((left_bits >> 1) | (right_bits >> 1)) & 1) << 1));
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    }
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#if USE_EMBEDDED_COMPILER
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    static constexpr bool compilable = false;
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#endif
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};
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struct NameBitBoolMaskAnd { static constexpr auto name = "__bitBoolMaskAnd"; };
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using FunctionBitBoolMaskAnd = BinaryArithmeticOverloadResolver<BitBoolMaskAndImpl, NameBitBoolMaskAnd>;
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}
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REGISTER_FUNCTION(BitBoolMaskAnd)
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{
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    factory.registerFunction<FunctionBitBoolMaskAnd>();
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}
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}
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