ee36358a60
these unused includes are identified by clang-include-cleaner. after auditing the source files, all of the reports have been confirmed. please note, since we have `using seastar::shared_ptr` in `seastarx.h`, this renders `#include <seastar/core/shared_ptr.hh>` unnecessary if we don't need the full definition of `seastar::shared_ptr`. so, in this change, all the unused includes are removed. but there are some headers which are actually used, while still being identified by this tool. these includes are marked with "IWYU pragma: keep". Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
73 lines
2.2 KiB
C++
73 lines
2.2 KiB
C++
/*
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* Modified by ScyllaDB
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*
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* Copyright (C) 2022-present ScyllaDB
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*/
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/*
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* SPDX-License-Identifier: (AGPL-3.0-or-later and Apache-2.0)
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*/
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#pragma once
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#include "function.hh"
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#include "stateless_aggregate_function.hh"
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namespace db {
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namespace functions {
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/**
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* Performs a calculation on a set of values and return a single value.
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*/
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class aggregate_function : public virtual function {
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protected:
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stateless_aggregate_function _agg;
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private:
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shared_ptr<aggregate_function> _reducible;
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private:
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static shared_ptr<aggregate_function> make_reducible_variant(stateless_aggregate_function saf);
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public:
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explicit aggregate_function(stateless_aggregate_function saf, bool reducible_variant = false);
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/**
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* Creates a new <code>Aggregate</code> instance.
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*
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* @return a new <code>Aggregate</code> instance.
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*/
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const stateless_aggregate_function& get_aggregate() const;
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/**
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* Checks whether the function can be distributed and is able to reduce states.
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*
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* @return <code>true</code> if the function is reducible, <code>false</code> otherwise.
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*/
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bool is_reducible() const;
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/**
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* Creates a <code>Aggregate Function</code> that can be reduced.
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* Such <code>Aggregate Function</code> returns <code>Aggregate</code>,
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* which returns not finalized output, but its accumulator that can be
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* later reduced with other one.
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*
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* Reducible aggregate function can be obtained only if <code>is_reducible()</code>
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* return true. Otherwise, it should return <code>nullptr</code>.
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*
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* @return a reducible <code>Aggregate Function</code>.
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*/
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::shared_ptr<aggregate_function> reducible_aggregate_function();
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virtual const function_name& name() const override;
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virtual const std::vector<data_type>& arg_types() const override;
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virtual const data_type& return_type() const override;
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virtual bool is_pure() const override;
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virtual bool is_native() const override;
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virtual bool requires_thread() const override;
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virtual bool is_aggregate() const override;
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virtual void print(std::ostream& os) const override;
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virtual sstring column_name(const std::vector<sstring>& column_names) const override;
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};
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}
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}
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