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42 lines
732 B
C++
42 lines
732 B
C++
#pragma once
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#include <DataStreams/IProfilingBlockInputStream.h>
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namespace DB
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{
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/** A stream of blocks from which you can read one block.
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* Also see BlocksListBlockInputStream.
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*/
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class OneBlockInputStream : public IProfilingBlockInputStream
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{
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public:
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OneBlockInputStream(const Block & block_) : block(block_) {}
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String getName() const override { return "One"; }
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String getID() const override
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{
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std::stringstream res;
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res << this;
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return res.str();
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}
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protected:
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Block readImpl() override
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{
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if (has_been_read)
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return Block();
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has_been_read = true;
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return block;
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}
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private:
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Block block;
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bool has_been_read = false;
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};
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}
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